Non-defining relative clause
Hanoi, which has a population of over eight million, faces serious congestion.
Extra information between commas; use which or who, never that.
FREE IELTS GRAMMAR CLINIC
More accuracy.
Less guesswork.
Tenses, articles, punctuation, linking words and complex sentences for IELTS, with a 12-point error clinic and three free quizzes.
HOW GRAMMAR IS MARKED
Grammatical Range and Accuracy is 25% of your Writing and Speaking score.
Examiners look for two things together: a mix of sentence types, and how many of your sentences are error-free. Long sentences full of mistakes score lower than clear, accurate ones.
01
Range
Simple, compound and complex sentences, with structures such as relative clauses, conditionals and the passive.
02
Accuracy
A high proportion of error-free sentences. Articles, plurals, agreement and tenses matter.
03
Punctuation
In Writing, full stops and commas in the right places so sentences have clear boundaries.
FOCUS: SUBORDINATION
Combine ideas clearly
Use because, although, whereas, if and while to create relationships between ideas — not simply longer sentences.
CLEAR RELATIONSHIP
Although the train was expensive, it was faster than the bus.
Why it works: Although signals contrast, and each clause has a clear subject and verb.
COMMON ERROR
Although the train was expensive, but it was faster.
Why to change it: In this structure, use although or but, not both together.
Try one sentence of your own
Use although to contrast two ideas about education and because to explain one of them. Read each sentence aloud. Is the relationship immediately clear?
TENSE MAP
Which tense, when?
Most tense errors in IELTS come from not matching the tense to the time in the question. Use this map.
| Situation | Tense | Example |
|---|---|---|
| Task 1: chart with past dates | Past simple | Sales fell sharply in 2015. |
| Task 1: future projections | will / is expected to / is projected to | The figure is projected to reach 40% by 2040. |
| Task 1: process with no dates | Present simple passive | The leaves are dried and then crushed. |
| Task 1: map of two years in the past | Past simple (often passive) | The trees were removed and a car park was built. |
| Task 2: general truths | Present simple | Technology changes the way people work. |
| Task 2: recent trends | Present perfect | Online shopping has grown rapidly in recent years. |
| Speaking Part 1: habits | Present simple | I usually cook at the weekend. |
| Speaking Part 2: a past story | Past simple + past continuous | I was walking home when I saw an old friend. |
| Speaking: from the past until now | Present perfect | I've lived in Hanoi since 2019. |
| Speaking Part 3: the future | will / might / be likely to | Robots might replace some routine jobs. |
ARTICLES: A, AN, THE OR NOTHING
One of the most common grammar errors in IELTS
Many learners' first languages, including Vietnamese and Chinese, have no articles, so these four rules make a quick difference.
a/an
First mention, one countable thing
The city built a new library.
the
Specific, known or unique
The library opened in 2020. The highest figure was in May.
Ø
General plural or uncountable
Children need exercise. Technology is changing education.
the
Fixed Task 1 phrases
the number of, the proportion of, the amount of, in the 1990s
COMMON ERROR
The technology has changed our lives.
This is technology in general, so it takes no article.
CORRECT
Technology has changed our lives.
Use the only for a specific technology: "the technology used in hospitals".
COUNTABLE AND UNCOUNTABLE NOUNS
Many or much? Fewer or less?
These common IELTS nouns are uncountable: they have no plural and cannot take a/an.
| Uncountable | To count it | Example |
|---|---|---|
| information, advice, evidence | a piece of… | She gave me a useful piece of advice. |
| research, knowledge, homework | a study, a fact, an assignment | Recent research suggests… / Several studies show… |
| equipment, furniture, traffic | an item of…, a car | There is too much traffic in the centre. |
| accommodation, transport, money | a flat, a bus, a dollar | Students need affordable accommodation. |
many / much
How many?
many students · much information
fewer / less
A smaller amount
fewer cars · less pollution
number / amount
In Task 1
the number of visitors · the amount of water
SENTENCE BOUNDARIES
Where one sentence ends and the next begins
Two complete sentences joined only by a comma (a "comma splice") is one of the most frequent errors in IELTS essays.
COMMA SPLICE
Many people work from home, this saves time.
Two full sentences need more than a comma between them.
THREE FIXES
…from home. This saves time. / …from home, which saves time. / Because many people work from home, they save time.
01
However
Start a new sentence: "However, costs are high." Mid-sentence it needs two commas: "Costs, however, are high."
02
No fragments
"Because it is expensive." is not a full sentence. Join it: "Few people buy it because it is expensive."
03
Commas after openers
Use a comma after an opening clause or linker: "Although it is costly, …", "In addition, …".
LINKING WORDS
Same meaning, different grammar
Linking words with the same meaning follow different rules. Choose the column, then follow its pattern.
| Function | Joins two clauses | Starts a new sentence | + noun or -ing |
|---|---|---|---|
| Contrast | although, while, whereas | However, / Nevertheless, | despite, in spite of |
| Reason | because, since, as | — | because of, due to |
| Result | so | Therefore, / As a result, / Consequently, | — |
| Addition | and | Moreover, / In addition, / Furthermore, | as well as, in addition to |
| Example | — | For example, / For instance, | such as |
Watch out: never write "despite of". Use despite + noun (despite the cost) or despite the fact that + clause. And avoid starting every sentence with a linker: examiners reward natural linking, not long lists of connectors.
COMPLEX SENTENCES
Six structures that show range
Use each one where it fits the meaning. One accurate complex sentence per paragraph is a good target.
Participle clause
Living in a large city, young people have more job opportunities.
The subject of both parts must be the same (young people live in the city).
Second conditional
If public transport were free, more people would leave their cars at home.
If + past simple, would + verb: for unlikely or imaginary situations.
Noun clause
What concerns many parents is the amount of time children spend online.
A clause used as the subject or object of the sentence.
It is … that
It is widely believed that exercise improves concentration.
A formal way to report opinions in Task 2 introductions.
The more…, the more…
The more cities grow, the more pressure they put on housing.
Shows that two changes happen together.
| Level | Sentence |
|---|---|
| Simple | Public transport is cheap. Many people use it. |
| Compound | Public transport is cheap, so many people use it. |
| Complex | Because public transport is cheap, many people use it. |
| Complex + precise | Since public transport is relatively cheap, it is used by a large proportion of city residents, particularly students. |
FREE GRAMMAR MINI-COURSE
12 sentence patterns worth practising
Understand the rule, study a meaningful IELTS-style sentence and then practise. These examples complement the IELTS4US Writing Grammar Workbook and remain free to everyone.
Subject–verb agreement
The proportion of students was 24%.
The proportion … was (singular noun “proportion”), not were.
Percentages
Thirty per cent of the students were absent.
The verb agrees with the noun after “of” when the percentage describes a group.
Tense for dated charts
The figure rose between 2010 and 2025.
Use past simple for completed past time periods.
Comparatives
Bus use was higher than car use.
Use comparative + than; do not write “more higher”.
Fractions
Almost a quarter of the total came from cycling.
A quarter ≈ 25%; choose approximations accurately.
Percentage-point change
Cycling rose by 14 percentage points.
“By” introduces the size of a change; share differences use percentage points.
Concession
Although the policy is costly, it could improve access.
Although + clause, main clause; do not add “but” after it.
Cause and effect
Travel costs fell because students stayed at home.
Because introduces the reason; therefore introduces the result.
Conditional
If universities offer seminars, students may feel less isolated.
If + present simple, modal + base verb is a practical conditional.
Passive voice
A new campus was built near the station.
Passive = be + past participle, useful for processes and maps.
Relative clause
Students who live far away benefit from online lectures.
Who refers to people; which refers to things.
Hedging
This policy may reduce traffic in city centres.
Use may, might or could to avoid claiming unproven certainty.
INSTANT FEEDBACK · TEN QUESTIONS
Accuracy clinic: the longer quiz
Sentence transformation practice
Task A: Join “Online classes can save time” and “Some learners need more interaction” using although.
Show one possible answer
Although online classes can save time, some learners need more interaction.
Task B: Change to passive: “The council built a new bus station in 2022.”
Show one possible answer
A new bus station was built by the council in 2022.
Task C: Correct the error: “The share of bus passengers were more higher in 2010.”
Show one possible answer
The share of bus passengers was higher in 2010.
The full IELTS4US Grammar Workbook develops eighteen units with 233 drills and explained answers.
ERROR CLINIC
12 grammar mistakes to check in every essay
Read your last essay once for each line in this table. Most students find at least three of these.
| Avoid | Write | Rule |
|---|---|---|
| Despite of the cost, … | Despite the cost, … | despite takes no of. |
| Although it is cheap, but… | Although it is cheap, … | Use one contrast word, not two. |
| The number of cars are rising. | The number of cars is rising. | The subject is the number (singular). |
| Many student / one of the main reason | Many students / one of the main reasons | Plural after many and one of the. |
| There are many people think… | Many people think… / There are many people who think… | A sentence needs one main verb. |
| If I will have time, … | If I have time, … | No will in the if clause. |
| I live here since 2019. | I have lived here since 2019. | From the past until now: present perfect. |
| It is depend on… | It depends on… | depend is a verb, not an adjective. |
| He suggested me to study. | He suggested that I study. / He suggested studying. | suggest is not followed by person + to. |
| The technology is important. | Technology is important. | No article for things in general. |
| Many people work at home, this saves time. | …at home, which saves time. | A comma cannot join two sentences. |
| The grapes picked by hand. | The grapes are picked by hand. | The passive needs be + past participle. |
PRACTICE · 8 QUESTIONS