By English Test Coach · Updated
Coherence and cohesion · Task 1 and Task 2
IELTS cohesive devices (linking words) with examples
Short answer: cohesive devices are the words and structures that connect your ideas, mainly linking words (“however”, “therefore”), reference words (“this”, “they”) and repeated key terms. Use each one because it shows a real relationship between ideas. Counting them, or opening every sentence with one, makes cohesion worse, not better.
This guide is published by English Test Coach, which makes the writing checker mentioned below. All examples are original teaching material. Bands mentioned come from the public band descriptors, which we summarise in our own words; any estimate of your writing is a practice estimate, not an official score.
The four kinds of cohesive device
Linking words get the attention, but they are only one of four tools. A paragraph that reads smoothly usually mixes all four.
| Kind | What it does | Example |
|---|---|---|
| Linking words and phrases | Show how one idea relates to another. | The ticket was cheap; however, the journey was slow. |
| Reference words | Point back to something already mentioned, so you do not repeat it. | The council closed two libraries. This decision upset many readers. |
| Substitution and ellipsis | Replace or leave out words the reader can supply. | Some pupils prefer maths and others, science. |
| Repeated key words and synonyms | Keep the topic visible from sentence to sentence. | Cycle lanes cost money. Safer lanes, however, can reduce injuries. |
Cohesion works inside sentences and between them. Coherence is the wider question of whether the whole text is organised so that a reader can follow it: a clear order of ideas, one main idea per paragraph and a visible line of argument. Linking words cannot rescue a disordered plan, which is why planning comes first.
Linking words by what they do
Choose the link from the relationship you want to show, not from a list of favourites. The same idea can often be expressed with a linking word, a reference word or no link at all.
| Job | Useful words | In a sentence |
|---|---|---|
| Adding | also, in addition, as well as, furthermore | The course is inexpensive. In addition, it can be completed online. |
| Contrasting | however, whereas, while, in contrast, on the other hand | Some learners study best in the morning, whereas others prefer the evening. |
| Conceding | although, even though, despite, in spite of | Despite the long journey, most visitors enjoyed the trip. |
| Giving a reason | because, since, as, due to, owing to | The library closed early because the heating failed. |
| Showing a result | therefore, as a result, consequently, so | The heating failed. As a result, the library closed early. |
| Giving an example | for example, for instance, such as | Public services, such as libraries, depend on local funding. |
| Showing a condition | if, unless, provided that, as long as | Fewer people will drive provided that buses are frequent. |
| Ordering steps | first, then, after that, finally, once | The paper is first sorted; it is then mixed with water. |
| Summing up | overall, in conclusion, to sum up | Overall, the benefits outweigh the costs. |
In Task 1, the useful links are mostly contrast and comparison (“whereas”, “while”, “respectively”), sequence for a process, and “overall” to introduce the overview. See them in context in the bar chart sample answer and the pie chart sample answer. In Task 2, reason, result, concession and example links carry the argument; the three full answers on the agree or disagree page show them at work.
Reference words: the quiet half of cohesion
Reference words let you move on without repeating yourself. They also hold sentences together, because the reader has to look back to find what the word means.
- Pronouns: “Cities that build cycle lanes often see fewer car trips. They also tend to have cleaner air.” “They” refers to the cities, so check that the noun is easy to find.
- This / these + a noun: “The council raised bus fares. This decision hit commuters hardest.” Naming the noun makes the reference clear. A bare “This is bad” leaves the reader guessing what “this” is.
- Such + noun: “Free fares might attract new passengers. Such a policy would still need funding.”
- Substitution: “Older drivers often prefer a quiet route; younger ones may prefer the fastest.” “Do so” works the same way: “Students who want to improve can do so by revising one paragraph at a time.”
- Repetition and synonyms: repeat a key term when the exact meaning matters, and use a close synonym when it does not. Changing “enrolments” to “registrations” is fine; changing “fares” to “taxes” changes the meaning.
The public descriptors mention reference words by name at band 7, and warn at band 6 that referencing can cause repetition. In practice: use a pronoun when the noun is obvious, a noun phrase when it is not, and avoid chains of “it” and “this” with no clear target.
Four traps that hurt cohesion
Weak: The train is faster, however it is more expensive.
Better: The train is faster; however, it is more expensive. (or: The train is faster. However, it is more expensive.)
“However” cannot join two sentences with only a comma. Use a full stop or a semicolon before it.
Weak: Although the bus was late, but we arrived on time.
Better: Although the bus was late, we arrived on time.
“Although” and “but” do the same job. Use one of them.
Weak: Because of the heating failed, the library closed.
Better: Because the heating failed, the library closed. (or: Because of the heating failure, the library closed.)
“Because of” takes a noun phrase; “because” takes a full clause.
Weak: In conclusion, I like cities. Moreover, they are big. Furthermore, they have shops.
Better: Cities appeal to me because they offer a wide choice of jobs and shops.
A connector that does not match the logic, or that opens every sentence, adds noise instead of clarity.
How cohesive devices affect your Coherence and cohesion estimate
Coherence and cohesion is one of four criteria of equal weight in IELTS Writing. In our own words, the public descriptors say that at band 6 cohesion is present but can be faulty or mechanical, and at band 7 a range of linking devices, including reference words, is used flexibly with some over- or under-use. The full wording is in the official band descriptors (PDF); our plain-English summary is in the band descriptors guide.
The same four sentences about libraries show the three situations a reader notices:
Underused
Libraries are useful. Many people cannot afford books. Libraries lend books for free. Some libraries have closed. Councils have less money.
Every idea is separate. The reader has to work out how they connect.
Mechanical
Firstly, libraries are useful. Secondly, many people cannot afford books. Moreover, libraries lend books for free. Furthermore, some libraries have closed. In addition, councils have less money.
Every sentence has a connector, yet none shows a real relationship. “In addition” should show a reason for the closures, which is a cause, not an extra item.
Natural
Libraries are useful because they lend books to people who cannot afford to buy them. Unfortunately, some have closed since councils now have less money to spend. This is a problem for the readers who relied on them most.
Fewer connectors, but each one carries meaning (“because”, “since”, “this”).
The natural version is not better because it has fewer links. It is better because every link is accurate and some relationships are carried by clause structure and reference words. English Test Coach's checker reports an estimated band for each of the four criteria, including Coherence and cohesion, as a practice estimate and not an official score. Automated tools tend to be better at spotting overused linking words and missing paragraphs than at judging how well an argument flows, so treat the estimate as one input: how accurate is AI scoring of Coherence and cohesion?
If you keep landing on the same number, read stuck at band 6: how to find what to fix next to decide whether cohesion is really the criterion holding you back.
Rewrite practice: from mechanical to natural
Rewrite this paragraph
Firstly, remote work saves time. Secondly, remote work saves money. Moreover, remote work is flexible. In addition, remote work has problems. Furthermore, workers feel lonely. In conclusion, remote work is good.
- Combine the first three sentences into one or two, using a reason link such as “because”.
- Choose the single link that shows the contrast with the problems.
- Replace the repeated “remote work” with a reference word where the meaning stays clear.
- Make the last sentence a conclusion that your paragraph actually supports.
Compare one possible rewrite
“Remote work saves both time and money because employees no longer commute, and it lets them arrange the day around their own tasks. However, it has drawbacks: some workers feel lonely without colleagues. Overall, the benefits seem to outweigh this problem, provided that firms organise regular meetings.”
“Because” links the reason, “However” marks the contrast, “this problem” refers back to loneliness and “provided that” states a condition. There are four links in three sentences, and each one is doing a job.
Check your own writing
- Does each link match the relationship (addition, contrast, reason, result, example)?
- Do fewer than half of your sentences begin with a connector?
- Is every “this” or “it” followed by, or clearly pointing to, one specific idea?
- Have you avoided joining two sentences with only a comma and “however” or “therefore”?
- Does each paragraph have one main idea that the first sentence names?
Questions about IELTS cohesive devices
What are cohesive devices in IELTS Writing?
Cohesive devices are the words and structures that connect ideas within and between sentences: linking words such as “however” and “therefore”, reference words such as “this” and “they”, substitution and ellipsis, and repeated key words or synonyms. They are one part of the Coherence and cohesion criterion, which also looks at logical order and paragraphing.
How many linking words should I use in an IELTS essay?
There is no right number. Use a link when the relationship between two ideas would otherwise be unclear, and let reference words and clear sentence order do the rest. The public descriptors treat both overuse and underuse as weaknesses.
Does using more linking words give a higher band?
No. The public descriptors describe cohesion that is faulty or mechanical at band 6 and a range of devices used flexibly at band 7, with some over- or under-use. A connector that does not match the logic, or that begins every sentence, works against you.
Are “firstly, secondly, finally” a problem?
Not by themselves. In a process description or a clearly ordered list they can be accurate. They become mechanical when every paragraph starts with the same sequence word and the words do nothing to show how the ideas relate.
Practise cohesion on a full answer
Write a Task 1 report or a Task 2 essay, then check how your links, references and paragraphs read. AI feedback is available in the workspace (allowances apply); the planner, timer and word count are free without an account. Estimates are for practice and are not official scores.