Create cohesive writing through effective linking. Ensure logical flow and coherence.
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Strong writing is more than a collection of correct sentences. Readers need to follow your thinking from one idea to the next without effort, and they need to see how every part of your text fits into a unified whole. Two qualities make this possible: coherence and cohesion. These terms are often used interchangeably, but they refer to different aspects of how a text holds together. Understanding the distinction -- and learning how to achieve both -- is essential for producing writing that communicates clearly and persuasively.
Cohesion refers to the linguistic links between sentences and clauses that make a text hang together on the surface. When a text is cohesive, each sentence connects to the ones around it through visible signals: repeated words, pronouns, conjunctions, and other linking devices.
Cohesion operates at the surface level of language. It is about the actual words and structures on the page that create connections.
The city council approved the new park design. It will include walking trails, a playground, and a community garden. These features were chosen based on a public survey conducted last spring.
In this example, cohesion is created by:
Without these links, the sentences would feel disconnected, even though they are all about the same topic.
Here is an important insight: a text can be cohesive without being coherent. Consider this example:
Maria enjoys hiking. Hiking trails are often found in national parks. National parks receive funding from the federal government. The federal government also funds space exploration. Space exploration has led to many technological advances.
Every sentence is linked to the previous one through a repeated word or phrase. The text is highly cohesive -- each sentence picks up a word from the last. But the passage makes no sense as a unified piece of writing. It starts with Maria's hobby and ends with space technology. There is no single idea holding it together. The text has cohesion but lacks coherence.
Coherence refers to the overall sense of unity and logical flow in a text. When a text is coherent, the reader can identify a clear purpose and follow the writer's reasoning from beginning to end. Every paragraph contributes to the main argument, and every sentence within a paragraph contributes to that paragraph's main idea.
Coherence operates at a deeper level than cohesion. It is about the underlying logic and organization of ideas, not just the surface-level links between sentences.
Maria enjoys hiking because it combines physical exercise with time in nature. She finds that walking through forests and along mountain trails reduces her stress levels significantly. Several studies support her experience: research published in Environmental Health and Technology found that spending two hours per week in natural settings leads to measurable improvements in mental well-being. For Maria, a weekend hike is not just recreation -- it is an essential part of maintaining her health.
This paragraph is coherent because every sentence develops a single idea: hiking benefits Maria's well-being. The reader never wonders why a particular sentence is there. The logic flows naturally from personal experience to scientific evidence to a concluding statement.
A text can also be coherent without being fully cohesive. Consider:
The school needs a new gymnasium. The current facility was built in 1974 and has not been renovated since. Enrollment has doubled in the past fifteen years. Basketball and volleyball teams currently practice in shifts because there is not enough court time. A bond measure on the November ballot would fund construction.
This paragraph is coherent -- every sentence supports the claim that the school needs a new gymnasium, and the reader can follow the argument. But the sentences are somewhat disconnected on the surface. There are no transitional words, no pronouns linking back to previous sentences, and no repeated key terms tying the text together. Adding cohesive devices would make the passage smoother to read.
The strongest writing achieves both coherence and cohesion simultaneously. Coherence provides the deep structure -- the logical organization and unity of purpose. Cohesion provides the surface structure -- the linguistic ties that guide the reader from sentence to sentence.
| Quality | Level | What It Does | Without It |
|---|---|---|---|
| Coherence | Deep structure | Makes the text logical and unified | The reader cannot follow the argument or identify the purpose |
| Cohesion | Surface structure | Links sentences together visibly | The text feels choppy, disconnected, or hard to read smoothly |
Think of coherence as the blueprint of a building and cohesion as the mortar between the bricks. The blueprint ensures that every room is in the right place and serves the building's purpose. The mortar holds the individual bricks together so the walls are solid. You need both: a building with a perfect blueprint but no mortar will collapse, and a building with strong mortar but no blueprint will be a maze of random rooms.
Coherence and cohesion are explicitly assessed in most academic writing rubrics. The IELTS Writing band descriptors, for example, dedicate an entire scoring criterion to "Coherence and Cohesion," evaluating how well ideas are organized and how effectively cohesive devices are used. TOEFL and AP English rubrics similarly reward logical organization and clear connections between ideas.
Writers who produce coherent, cohesive essays score higher because their arguments are easier to follow. A grader who has to re-read sentences to understand the connection between ideas will perceive the writing as less persuasive, even if the individual points are strong.
In business and professional contexts, coherence and cohesion directly affect how quickly a reader can extract information. A coherent report allows a busy executive to skim the headings and topic sentences and understand the argument. Cohesive transitions ensure that the reader does not lose the thread between sections.
Poorly organized writing wastes the reader's time and undermines the writer's credibility. If a proposal jumps between topics without clear connections, the reader may conclude that the writer's thinking is similarly disorganized.
Even in emails, messages, and informal writing, coherence and cohesion matter. A disjointed email that jumps between requests, questions, and observations without clear organization is harder to respond to and more likely to be misunderstood. Structuring your thoughts logically and linking them clearly makes all communication more effective.
The remaining sections of this module cover the specific tools and strategies for achieving cohesion and coherence:
| Section | Focus |
|---|---|
| Cohesive Devices | The linguistic tools that link sentences: reference, substitution, ellipsis, conjunction, lexical cohesion |
| Building Coherence | The organizational strategies that create logical flow: ordering, given-new information, thematic progression |
| Coherence and Cohesion in Practice | Before-and-after examples showing how to improve real paragraphs |
| Reference Guide | Device categories, common problems, and a self-editing checklist |
Mastering these tools will not only improve your writing scores but also make your writing more effective in any context -- academic, professional, or personal.
| Concept | Definition | Level | Key Question |
|---|---|---|---|
| Cohesion | Linguistic links between sentences (pronouns, transitions, repetition) | Surface | Are the sentences connected to each other? |
| Coherence | Logical unity and flow of ideas throughout the text | Deep | Does the text make sense as a whole? |
| Both together | Cohesion + coherence = writing that is both smooth and logical | Complete | Is the text easy to follow AND purposeful? |
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Cohesive devices are the specific linguistic tools that tie sentences and clauses together, creating visible connections across a text. The linguist M.A.K. Halliday identified five major categories of cohesive devices: reference, substitution, ellipsis, conjunction, and lexical cohesion. Understanding each category gives you a toolkit for making your writing flow smoothly from one sentence to the next.
Reference occurs when one word or phrase in a text points to another word or phrase elsewhere in the text (or in the shared context). The most common referencing devices are pronouns and demonstratives.
Pronouns replace nouns to avoid repetition and create links between sentences.
Dr. Patel conducted the study over three years. She collected data from 500 participants across four countries. Her findings challenged several widely held assumptions about sleep patterns.
"She" and "Her" refer back to "Dr. Patel," linking all three sentences.
Demonstratives point to specific items mentioned earlier in the text.
The committee proposed cutting funding for after-school programs. This decision drew immediate criticism from parents and teachers.
"This decision" refers back to the entire previous sentence, creating a clear link.
Important: When using "this" or "these" as reference words, always attach a noun after them. Bare "this" can be ambiguous.
Ambiguous: The report revealed declining enrollment, budget shortfalls, and staff turnover. This concerned the board. (What concerned the board -- all three issues? One of them?)
Clear: The report revealed declining enrollment, budget shortfalls, and staff turnover. This combination of problems concerned the board.
Comparative references link items by indicating similarity or difference.
Last year's revenue was $2.4 million. This year's figure is expected to exceed that amount by at least 15%.
"This year's figure" and "that amount" create reference links to the previous sentence.
The word "the" signals that the reader should already know which item is being discussed -- often because it was introduced earlier.
A new policy was announced last week. The policy requires all employees to complete cybersecurity training by December.
The shift from "a new policy" (introducing something new) to "the policy" (referring to something already known) is itself a cohesive device.
Substitution replaces a word, phrase, or clause with a substitute form to avoid repetition while maintaining the connection. The most common substitution words are one, ones, do, so, and not.
I need a new laptop. My current one is too slow for video editing.
"One" substitutes for "laptop."
These results are promising, but the earlier ones were inconclusive.
"Ones" substitutes for "results."
The manager asked the team to submit their reports by Friday. Only three members did so.
"Did so" substitutes for "submitted their reports by Friday."
I expected the experiment to confirm our hypothesis. It did not.
"Did not" substitutes for "did not confirm our hypothesis."
Will the project be completed on time? I believe so.
"So" substitutes for the entire clause "the project will be completed on time."
Is the data reliable? There is no reason to think not.
"Not" substitutes for "the data is not reliable."
Ellipsis is the omission of words that can be understood from context. Rather than replacing a word with a substitute (as in substitution), ellipsis simply leaves a gap that the reader fills in mentally.
Both proposals have merit, but the second [proposal] is more practical.
The word "proposal" is omitted because the reader understands it from context.
Some students completed the assignment on time; others did not [complete the assignment on time].
The verb phrase is omitted from the second clause.
Who approved this decision? -- The director [approved this decision].
The full clause is unnecessary because the question establishes the context.
Ellipsis is more common in speech and informal writing than in academic prose. In formal writing, use it sparingly and only when the omitted material is completely obvious from context. Overuse can make writing feel choppy or unclear.
Conjunction uses linking words and phrases to signal the logical relationship between sentences or clauses. Unlike reference, substitution, and ellipsis (which create backward-looking links), conjunctions often signal what is coming next.
Conjunctive devices fall into four main categories:
Signal that the next idea adds to or aligns with the previous one.
| Conjunction | Example |
|---|---|
| and, also, furthermore | The program improved test scores. Furthermore, it increased student engagement. |
| moreover, in addition | The cost is reasonable. In addition, the implementation timeline is realistic. |
| similarly, likewise | Urban schools face overcrowding. Similarly, rural schools struggle with underfunding. |
Signal contrast, concession, or opposition.
| Conjunction | Example |
|---|---|
| but, however, yet | The results were promising. However, the sample size was too small to draw firm conclusions. |
| on the other hand, in contrast | Proponents argue the policy saves money. On the other hand, critics say it reduces service quality. |
| nevertheless, nonetheless | The evidence is limited. Nevertheless, the trend is worth monitoring. |
Signal cause and effect, reason, or purpose.
| Conjunction | Example |
|---|---|
| so, therefore, consequently | Enrollment dropped by 20%. Consequently, the university reduced its adjunct faculty budget. |
| because, since, as a result | Sales declined for the third consecutive quarter. As a result, the company initiated a restructuring plan. |
| thus, hence, for this reason | The bridge is structurally unsound. For this reason, it has been closed to heavy vehicles. |
Signal time relationships and sequence.
| Conjunction | Example |
|---|---|
| then, next, afterward | The team collected the data. Next, they coded the responses into categories. |
| first, second, finally | First, participants completed a survey. Then, they were interviewed individually. |
| meanwhile, subsequently | The investigation continued for six months. Meanwhile, the company operated under interim leadership. |
Conjunctions are among the most visible cohesive devices, and they are the ones writers most commonly overuse or misuse. Key principles:
Choose the right conjunction. A "however" signals contrast; if you mean "in addition," use an additive conjunction. Using the wrong conjunction confuses the reader about the logical relationship.
Vary your conjunctions. Repeating "however" or "furthermore" in every paragraph becomes monotonous. Use the full range of options.
Do not overuse conjunctions. Not every sentence needs an explicit conjunction. When the logical relationship is obvious, let the sentences speak for themselves. Over-connectorizing makes writing feel mechanical.
Over-connected: The study had several limitations. However, the results are still useful. Moreover, they align with previous research. Furthermore, the methodology was sound. Therefore, the conclusions are reliable.
Better: The study had several limitations, but the results are still useful. They align with previous research, and the methodology was sound enough to support the conclusions.
Lexical cohesion creates connections through word choice rather than grammatical devices. There are two main types: reiteration and collocation.
Reiteration involves repeating or restating a concept using the same word, a synonym, a superordinate (broader category), or a general noun.
| Type | Example |
|---|---|
| Exact repetition | The experiment yielded unexpected results. The experiment was then repeated with a larger sample. |
| Synonym | The experiment yielded unexpected results. The study was then repeated with a larger sample. |
| Superordinate | The experiment yielded unexpected results. The research was then expanded. |
| General noun | The experiment yielded unexpected results. This finding prompted further investigation. |
Exact repetition is the strongest cohesive tie but can become monotonous. Mixing repetition with synonyms and general nouns keeps the text cohesive without being repetitive.
Collocation refers to words that commonly occur together in a given topic or context. When readers encounter words that belong to the same semantic field, they sense cohesion even without explicit links.
The surgeon prepared for the operation. The anesthesiologist checked the patient's vital signs. Nurses arranged the instruments on the sterile tray. The operating room was quiet except for the steady beep of the heart monitor.
The words "surgeon," "operation," "anesthesiologist," "patient," "vital signs," "nurses," "instruments," "sterile," "operating room," and "heart monitor" all belong to the semantic field of surgery. Their co-occurrence creates strong lexical cohesion.
Effective cohesion comes from using a mix of devices, not relying on any single type.
| Situation | Best Devices |
|---|---|
| Referring back to a person or thing | Pronouns, demonstratives, definite article |
| Avoiding repetition of a noun | Substitution, synonyms, general nouns |
| Showing logical relationships | Conjunctions (additive, adversative, causal, temporal) |
| Maintaining topic focus | Exact repetition of key terms, collocation |
| Keeping sentences concise | Ellipsis, substitution |
The goal is not to use as many cohesive devices as possible. The goal is to use them where they are needed -- where the reader might otherwise lose the connection between ideas.
| Device | What It Does | Examples |
|---|---|---|
| Reference | Points to something mentioned elsewhere | he, she, it, this, these, the |
| Substitution | Replaces a word/phrase with a substitute | one, do so, not |
| Ellipsis | Omits words recoverable from context | "Some did; others didn't [do it]" |
| Conjunction | Signals logical relationships | however, therefore, in addition, first |
| Lexical cohesion | Creates links through word choice | repetition, synonyms, collocations |
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While cohesion operates at the surface level through linguistic devices, coherence operates at a deeper level through the logical organization and flow of ideas. A coherent text feels purposeful: the reader always knows where the argument is going and why each piece of information appears where it does. This section covers three core strategies for building coherence: logical ordering, given-new information flow, and thematic progression.
The most fundamental way to create coherence is to arrange your ideas in an order that the reader can follow intuitively. When ideas are presented in a logical sequence, the text feels natural even before you add any cohesive devices.
| Order Type | How It Works | Best For |
|---|---|---|
| Chronological | Events in the order they happened | Narratives, process descriptions, historical accounts |
| Spatial | Details arranged by physical location | Descriptions of places, scenes, objects |
| Order of importance | Most important to least, or least to most | Arguments, persuasive writing |
| General to specific | Broad claim followed by narrowing details | Academic paragraphs, explanatory writing |
| Specific to general | Specific examples building to a broad conclusion | Inductive arguments |
| Problem-solution | Problem described first, then solution proposed | Reports, proposals, persuasive essays |
| Cause-effect | Cause described first, then its effects (or reverse) | Analytical writing, science, social commentary |
| Compare-contrast | Two or more items examined for similarities/differences | Evaluative writing, analysis |
Consider these two versions of the same paragraph:
Version A (logical order):
The company's decline began with a series of poor strategic decisions. In 2018, management invested heavily in a product line that market research had already shown was losing consumer interest. By 2019, the product had failed to gain traction, and the company was forced to write off $50 million in development costs. The following year, in an effort to cut losses, the company laid off 20% of its workforce, which further damaged morale and productivity. By 2021, the company's stock price had fallen to a third of its 2017 peak.
Version B (disorganized):
The company's decline began with a series of poor strategic decisions. The company's stock price fell to a third of its 2017 peak by 2021. In 2019, the product failed to gain traction. Management invested heavily in a losing product line in 2018. The company laid off 20% of its workforce in 2020, which damaged morale.
Both versions contain the same information. Version A is coherent because it follows chronological order -- each event leads logically to the next. Version B jumps between years, making it difficult for the reader to follow the chain of cause and effect.
The best ordering depends on your purpose:
The key question to ask: "What does the reader need to know first in order to understand what comes next?" Arrange your ideas so that each sentence builds on the knowledge the reader has already gained.
One of the most powerful tools for building coherence is the given-new principle. This principle states that each sentence should begin with given information (something the reader already knows) and end with new information (something the reader is learning for the first time).
When a sentence starts with familiar information, the reader has an anchor -- a stable point from which to process the new content. When a sentence starts with entirely new information, the reader has to work harder to figure out how it connects to what came before.
Following the given-new principle:
(1) Solar panels convert sunlight into electricity. (2) This electricity can be stored in batteries for use at night. (3) Battery storage technology has improved dramatically in the past decade. (4) These improvements have made solar energy a viable alternative to fossil fuels in many regions.
In each sentence, the beginning (bold italic) picks up something from the previous sentence:
The result is a smooth chain where each sentence flows naturally into the next.
Violating the given-new principle:
(1) Solar panels convert sunlight into electricity. (2) Dramatic improvements have occurred in battery storage technology over the past decade. (3) Many regions now consider solar energy a viable alternative to fossil fuels. (4) Batteries can store the electricity for use at night.
The same information is present, but the sentences are harder to follow because each one begins with new information rather than connecting to the previous sentence.
The given-new principle also operates between paragraphs. The first sentence of a new paragraph should connect to something from the previous paragraph (given) before introducing the new paragraph's topic (new).
End of Paragraph 1: ...These cost savings make solar energy increasingly attractive to homeowners.
Start of Paragraph 2: Beyond the financial benefits for individual homeowners, solar energy adoption also produces significant environmental gains at the community level.
The phrase "Beyond the financial benefits for individual homeowners" acknowledges what the reader just learned (given) before introducing the new topic (environmental gains).
When revising, check each sentence opening:
Thematic progression describes the pattern by which the themes (starting points) and rhemes (new information) of successive sentences develop across a text. Understanding these patterns helps you control the flow of information and maintain coherence over longer passages.
The new information in one sentence becomes the starting point of the next. This creates a chain-like progression.
Word IvySentence 1: Theme 1 → Rheme 1
Sentence 2: Theme 2 (= Rheme 1) → Rheme 2
Sentence 3: Theme 3 (= Rheme 2) → Rheme 3
(1) The researchers developed a new vaccine. (2) The vaccine was tested on 10,000 volunteers. (3) The volunteers reported only mild side effects. (4) These side effects disappeared within 48 hours.
Each sentence picks up the new element from the previous sentence and uses it as the starting point. This pattern is excellent for explaining processes, tracing cause-and-effect chains, and building narratives.
The same theme (subject) is maintained across several sentences, with different new information added each time.
Sentence 1: Theme 1 → Rheme 1
Sentence 2: Theme 1 → Rheme 2
Sentence 3: Theme 1 → Rheme 3
(1) The new library will be located on the corner of Main and Oak streets. (2) It will feature three floors of open reading space. (3) The building will also include a children's wing, a technology lab, and a community meeting room. (4) It is expected to open in September 2027.
The same subject (the new library) is the starting point of every sentence, with new information about location, features, and opening date added progressively. This pattern works well for describing a single subject in detail.
Multiple sentences share a common "hypertheme" (overarching topic), and each sentence introduces a different sub-topic derived from that hypertheme.
Hypertheme: "The city faces three major challenges"
Sentence 1: Sub-theme A (challenge 1) → Rheme
Sentence 2: Sub-theme B (challenge 2) → Rheme
Sentence 3: Sub-theme C (challenge 3) → Rheme
The city faces three major infrastructure challenges. The roads are deteriorating faster than maintenance budgets can keep up with. The water system relies on pipes that are over fifty years old and increasingly prone to leaks. The public transit network has not been expanded since 1995, despite a 40% increase in ridership.
The first sentence introduces the hypertheme (three challenges). Each subsequent sentence derives its theme from that overview: roads, water, transit. This pattern is effective for developing a claim that has multiple components.
In practice, skilled writers mix these patterns within and across paragraphs. A paragraph might begin with constant theme progression (describing one subject), shift to linear progression (tracing a cause-and-effect chain), and then use derived theme progression (listing components of a conclusion).
The key is awareness. When a passage feels disjointed, analyze the thematic progression. Often the problem is that themes shift unpredictably, with no clear pattern for the reader to follow.
The strategies above apply not only within paragraphs but across an entire essay.
The topic sentences of consecutive paragraphs should form a logical chain that a reader can follow even without reading the supporting details. If you read only the topic sentences of a well-organized essay, you should be able to understand the argument.
Topic sentence 1: Climate change is increasing the frequency of extreme weather events worldwide.
Topic sentence 2: These extreme weather events have devastating economic consequences for affected regions.
Topic sentence 3: The economic damage, in turn, disproportionately affects low-income communities that lack resources for recovery.
Topic sentence 4: Addressing this inequality requires targeted government investment in climate resilience for vulnerable populations.
Notice how each topic sentence picks up an element from the previous one, creating a coherent chain of reasoning across the essay.
Transitions between paragraphs serve a dual purpose: they provide cohesion (linguistic links) and signal coherence (logical relationships). A good transition tells the reader both what the connection is and why the new paragraph follows from the previous one.
| Transition Type | What It Signals | Example |
|---|---|---|
| Continuation | The next point adds to the previous one | "In addition to cost savings, renewable energy also offers..." |
| Contrast | The next point presents a different perspective | "While the benefits are clear, significant challenges remain..." |
| Consequence | The next point follows from the previous one | "As a result of these changes, communities have begun to..." |
| Elaboration | The next point develops the previous one in more detail | "A closer look at the data reveals..." |
| Strategy | What It Does | Key Principle |
|---|---|---|
| Logical ordering | Arranges ideas in a sequence the reader can follow | Each idea should build on what came before |
| Given-new information flow | Starts sentences with familiar info, ends with new info | Anchor the reader before introducing new content |
| Thematic progression | Controls how themes develop across sentences | Use linear, constant, or derived patterns consistently |
| Essay-level coherence | Ensures paragraphs form a logical chain | Topic sentences should tell the essay's story on their own |
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Theory becomes useful only when you can apply it. This section presents real before-and-after examples of paragraphs with coherence and cohesion problems, walks through the analysis of what went wrong, and shows how targeted revisions transform weak writing into strong, flowing prose.
Urban gardens provide many benefits. Fresh produce is available to residents. Food deserts are a problem in cities. Community bonds are strengthened. Exercise is a benefit of gardening. Mental health improves when people spend time outdoors. Cities should invest in urban gardens.
This paragraph has a clear topic (urban gardens are beneficial) and relevant supporting points. The problem is entirely one of cohesion -- the sentences are disconnected from each other. Each sentence reads like an isolated statement. The reader has to do all the work of figuring out how the ideas relate.
Specific problems:
Urban gardens provide a wide range of benefits to city residents. Most directly, they give people access to fresh produce -- a resource that is often scarce in urban food deserts, where grocery stores are few and convenience stores dominate. Beyond nutrition, these community spaces strengthen social bonds by bringing neighbors together around a shared activity. The physical act of gardening also offers regular, low-impact exercise, and the time spent outdoors among growing plants has been shown to reduce stress and improve mental health. Given these overlapping benefits, cities have a strong incentive to invest in urban garden programs.
The revised version uses:
Furthermore, education is important for economic growth. Moreover, it increases individual earning potential. In addition, education improves health outcomes. Additionally, educated populations tend to have lower crime rates. Also, education promotes civic participation. Therefore, governments should invest in education.
This paragraph has the opposite problem from Example 1. Every sentence begins with a conjunctive adverb (Furthermore, Moreover, In addition, Additionally, Also, Therefore). The writer is clearly trying to create cohesion, but the result feels mechanical and monotonous.
Specific problems:
Investment in education generates returns that extend far beyond the classroom. At the individual level, each additional year of schooling increases lifetime earnings by an estimated 8-13%, according to World Bank research. These higher earnings translate into broader economic benefits: educated workers are more productive, more innovative, and more adaptable to changing labor markets. The effects are not limited to economics, however. Communities with higher education levels consistently report better health outcomes, largely because educated individuals are more likely to seek preventive care and make informed health decisions. Perhaps most significantly, education strengthens the social fabric itself -- research shows that educated populations have lower crime rates and higher levels of civic participation, from voting to volunteering. Taken together, these findings make a compelling case for governments to treat education funding not as an expense but as an investment with measurable, multi-dimensional returns.
The revised version uses:
Climate change affects agriculture in many ways. Farmers in Southeast Asia are particularly vulnerable to rising sea levels. The European Union has invested billions in renewable energy. Droughts in sub-Saharan Africa have led to food shortages. Some scientists predict that crop yields will decline by 25% by 2050. Carbon capture technology is still in its early stages.
This paragraph has a topic sentence about climate change and agriculture, and most of the sentences are loosely related to climate change. But the paragraph lacks coherence -- there is no single controlling idea guiding the selection and arrangement of information.
Specific problems:
Climate change poses a serious and growing threat to global agricultural production. Rising temperatures and shifting rainfall patterns are already disrupting crop cycles in many parts of the world. In sub-Saharan Africa, prolonged droughts have reduced harvests and triggered food shortages affecting millions of people. In Southeast Asia, the situation is different but equally alarming: rising sea levels are inundating coastal farmland, contaminating soil with salt water and rendering once-productive fields unusable. Looking ahead, the outlook is stark -- some climate models predict that global crop yields could decline by as much as 25% by 2050 if current warming trends continue. These projections underscore the urgency of both reducing emissions and developing agricultural practices that can withstand a warmer, more volatile climate.
The revised version achieves coherence by:
Let us examine a well-written paragraph and identify every cohesive tie at work.
(1) The discovery of antibiotics in the early twentieth century transformed medicine. (2) Infections that had once been fatal -- pneumonia, tuberculosis, sepsis -- became treatable almost overnight. (3) Surgical procedures that doctors had previously avoided because of the risk of post-operative infection became routine. (4) Life expectancy in developed nations rose dramatically as a result. (5) However, the widespread and often careless use of these drugs over the following decades has created a new crisis: antibiotic-resistant bacteria. (6) These so-called "superbugs" now kill an estimated 1.27 million people per year worldwide, threatening to undo the very progress that antibiotics made possible.
| Tie | Type | Sentences Linked |
|---|---|---|
| "Infections" (related to "medicine") | Lexical cohesion (collocation) | 1 → 2 |
| "that had once been fatal" | Reference (relative clause pointing to "infections") | within 2 |
| "Surgical procedures" (related to "medicine") | Lexical cohesion (collocation) | 1 → 3 |
| "that doctors had previously avoided" | Reference (relative clause) | within 3 |
| "post-operative infection" → "infections" | Lexical cohesion (repetition/synonym) | 2 → 3 |
| "as a result" | Conjunction (causal) | 3 → 4 |
| "However" | Conjunction (adversative) | 4 → 5 |
| "these drugs" | Reference (demonstrative + synonym for "antibiotics") | 1 → 5 |
| "antibiotic-resistant bacteria" | Lexical cohesion (collocation with "antibiotics") | 1 → 5 |
| "These so-called superbugs" | Reference (demonstrative + synonym) | 5 → 6 |
| "the very progress that antibiotics made possible" | Lexical cohesion (repetition) + Reference | 1 → 6 |
This paragraph uses eleven cohesive ties in six sentences. The ties come from multiple categories -- reference, conjunction, and lexical cohesion -- creating a dense web of connections. No single device is overused, and the ties work together with the logical organization (chronological progression from discovery to overuse) to produce writing that is both cohesive and coherent.
Coherence and cohesion are not only about connections within paragraphs. The transitions between paragraphs are equally important.
Paragraph 1: ...Solar energy has become the cheapest source of electricity in most countries.
Paragraph 2: Wind power has grown rapidly in recent years.
The shift from solar to wind is abrupt. The reader wonders: Are we still talking about the same argument? How does wind power relate to what we just learned about solar?
Paragraph 1: ...Solar energy has become the cheapest source of electricity in most countries, but it is not the only renewable source that has seen dramatic growth.
Paragraph 2: Wind power, which now supplies over 7% of global electricity, has expanded even faster than solar in several key markets.
The revised version uses:
When you encounter writing that feels "off" but you cannot quite explain why, use this diagnostic process:
If any answer is "no," the problem is coherence. Fix the deep structure first.
If the structure is logical but the text still feels choppy, the problem is cohesion. Add appropriate linking devices.
If so, remove some conjunctions and let the logical connections speak for themselves.
| Problem | Symptom | Fix |
|---|---|---|
| Lacks cohesion | Sentences feel disconnected, choppy | Add pronouns, transitions, key term repetition |
| Over-connected | Reads like a mechanical list of connectors | Remove unnecessary conjunctions, vary sentence openings |
| Lacks coherence | Paragraph jumps between unrelated ideas | Remove off-topic sentences, establish logical order |
| Both problems | Confusing and hard to follow | Fix coherence first (structure), then add cohesion (links) |
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This section serves as a quick-access reference for everything covered in this module. Use it when writing, revising, or self-editing to check that your text is both coherent and cohesive.
| Device | Function | Examples |
|---|---|---|
| Personal pronouns | Replace nouns to avoid repetition | he, she, it, they, him, her, them |
| Possessive pronouns | Show ownership while linking back | his, her, its, their, my, our |
| Demonstratives | Point to specific items mentioned earlier | this, that, these, those (+ noun) |
| Definite article | Signal that the item is already known | the |
| Comparatives | Link items through comparison | more, less, fewer, better, the same, similar, different |
| Relative pronouns | Connect clauses to their referents | who, which, that, whose, where |
| Device | Replaces | Example |
|---|---|---|
| one / ones | Noun | "I need a new laptop. This one is broken." |
| do / did / does | Verb phrase | "She finished the report. He did too." |
| so | Positive clause | "Will it rain? I think so." |
| not | Negative clause | "Can we finish today? I hope not." |
| Category | Purpose | Devices |
|---|---|---|
| Additive | Adding information | and, also, furthermore, moreover, in addition, additionally, besides, likewise, similarly |
| Adversative | Contrasting or conceding | but, however, yet, nevertheless, nonetheless, on the other hand, in contrast, conversely, despite this, admittedly |
| Causal | Showing cause/effect | so, therefore, consequently, as a result, thus, hence, because, since, for this reason, accordingly |
| Temporal | Indicating time/sequence | first, second, then, next, afterward, subsequently, finally, meanwhile, previously, at the same time |
| Clarifying | Restating or specifying | in other words, that is, specifically, namely, to put it another way |
| Summarizing | Drawing together | in summary, to sum up, in short, overall, in brief, taken together |
| Device | How It Works | Example |
|---|---|---|
| Exact repetition | Same word repeated | "The policy failed. The policy was then revised." |
| Synonym | Different word, same meaning | "The policy failed. The regulation was then revised." |
| Superordinate | Broader category term | "The sedan broke down. The vehicle had to be towed." |
| General noun | Vague noun referring back | "Enrollment dropped. This trend continued for three years." |
| Collocation | Words from the same semantic field | "The surgeon entered the operating room. The anesthesiologist was already preparing the patient." |
| Pattern | Description | Signal Words |
|---|---|---|
| Chronological | Events in time order | first, then, next, afterward, in 2020, the following year |
| Order of importance | Strongest to weakest (or reverse) | most importantly, a more significant factor, above all |
| General to specific | Broad claim narrowed by details | specifically, in particular, for example |
| Specific to general | Details building to a broad claim | taken together, these examples show, this evidence suggests |
| Problem-solution | Problem stated, then solution proposed | the problem is, one solution, to address this |
| Cause-effect | Cause described, then effects | because of this, as a result, the consequence was |
| Compare-contrast | Similarities and differences examined | similarly, in contrast, unlike, whereas |
| Principle | How to Apply |
|---|---|
| Start with known info | Begin each sentence with something the reader already knows from previous sentences |
| End with new info | Place the most important new content at the end of the sentence |
| Bridge between paragraphs | Start each paragraph by connecting to the previous paragraph before introducing the new topic |
| Pattern | Structure | Best For |
|---|---|---|
| Linear (zigzag) | New info in sentence 1 becomes the theme of sentence 2 | Processes, cause-effect chains, narratives |
| Constant theme | Same subject across multiple sentences, with new info added | Describing one subject in detail |
| Derived themes | One overarching topic, with sub-topics in each sentence | Developing a multi-part claim |
Symptom: Sentences feel disconnected. Each sentence reads like a standalone statement.
Cause: Insufficient cohesive devices. No pronouns, transitions, or repeated terms linking sentences.
Solution:
Symptom: Every sentence begins with "However," "Furthermore," "Moreover," or "In addition." The text reads like a mechanical checklist.
Cause: Over-reliance on conjunctive devices while neglecting other cohesion types.
Solution:
Symptom: The reader cannot tell what "this," "it," or "they" refers to.
Cause: Pronouns used without clear antecedents, especially bare "this" or "it" after complex sentences.
Solution:
Symptom: The paragraph starts on one topic and gradually shifts to another without the reader noticing until it is too late.
Cause: Lack of coherence -- no clear controlling idea keeping the paragraph focused.
Solution:
Symptom: The reader has to re-read sentences to understand how they connect. Ideas seem to appear in random order.
Cause: No clear organizational pattern (chronological, order of importance, cause-effect, etc.).
Solution:
Symptom: The shift from one paragraph to the next feels abrupt. The reader wonders how the new topic connects to the previous one.
Cause: No forward-looking or backward-looking transitions between paragraphs.
Solution:
Use this checklist when revising any piece of writing. Work through it in order: fix coherence problems first (deep structure), then address cohesion (surface links).
| You Want To... | Use |
|---|---|
| Refer back to a noun without repeating it | Pronoun (he, she, it, they) |
| Point to a specific idea from the previous sentence | Demonstrative + noun (this finding, these results) |
| Show that you are adding another point | Additive conjunction (furthermore, in addition, also) |
| Show contrast or concession | Adversative conjunction (however, nevertheless, on the other hand) |
| Show cause and effect | Causal conjunction (therefore, as a result, consequently) |
| Show time or sequence | Temporal conjunction (first, then, subsequently, finally) |
| Avoid repeating the same word | Synonym, superordinate, or general noun |
| Create a sense of topic focus | Exact repetition of key terms + collocation |
| Make a sentence flow from the previous one | Given-new ordering (start with known, end with new) |
| Organize a paragraph logically | Choose an ordering pattern (chronological, importance, cause-effect) |
| Connect two paragraphs | Forward-looking transition + backward-looking opening |
For writers preparing for standardized writing assessments, here is how coherence and cohesion are typically evaluated:
| Assessment | What Graders Look For |
|---|---|
| IELTS (Band 7+) | Logical organization, clear progression, appropriate use of cohesive devices without over-reliance, each paragraph has a clear central topic |
| TOEFL (Score 4-5) | Well-organized response, appropriate transitions, unity and progression of ideas |
| AP English (Score 5-6) | Sophisticated control of organization, strategic use of transitions, coherent line of reasoning |
| Academic/Business | Professional structure, logical flow, reader can follow the argument on first reading |
In all cases, graders reward writing that the reader can follow without effort. Coherence and cohesion are the qualities that make that possible.
| Category | Key Principle |
|---|---|
| Cohesive devices | Use a mix of reference, substitution, ellipsis, conjunction, and lexical cohesion |
| Coherence strategies | Organize logically, follow given-new flow, use consistent thematic progression |
| Common problems | Choppy writing, over-connection, vague pronouns, topic drift, illogical order, missing transitions |
| Self-editing | Fix coherence first (structure), then cohesion (links), then read aloud |