One of the main reasons many IELTS candidates get stuck at Band 6.0–6.5 in Writing Task 2 is their limited ability to construct accurate, flexible, and meaningful complex sentences. Examiners do not want overly long or confusing sentences; instead, they expect a range of grammatical structures that are used accurately and naturally.
This guide reveals the essential complex structures you must master to reach Band 7 and beyond.
1. Why Complex Sentences Matter in the IELTS Writing Band Descriptors
According to official criteria, higher bands require:
- Grammatical range (variety of sentence types)
- Grammatical accuracy (minimal errors)
- Logical cohesion (ideas linked smoothly)
Simply put:
If you cannot write accurate complex sentences consistently, Band 7 is impossible.
2. Core Types of Complex Sentences You Must Master
(1) Adverb Clauses – Cause, Result, Contrast, Condition
These add depth and logical flow to arguments.
Useful structures:
- because / since / as
- although / even though
- if / unless
- while / whereas
Example:
Although the government has introduced several environmental policies, pollution levels continue to rise.
(2) Noun Clauses – Essential for Presenting Opinions
Use noun clauses after verbs like “believe”, “argue”, “claim”, “suggest”.
Examples:
- Experts argue that stricter regulations are necessary.
- It is widely believed that education plays a key role in reducing crime.
These are perfect for thesis statements.
(3) Relative Clauses – Add Precision and Academic Tone
Introduced by who, which, that, where.
Examples:
- The resources that governments invest in public transport directly affect urban mobility.
- People who live in rural areas often lack access to quality healthcare.
(4) Introductory Phrases – A Band 7+ Signature
Not technically clauses, but widely used in complex structures.
Examples:
- In addition to this,
- From a broader perspective,
- Despite widespread criticism,
These make your sentences sound more academic.
3. The “3-Tier Complex Sentence Method” (Easy Formula for Band 7+)
To avoid long, messy sentences, follow this structure:
Tier 1: Main idea
Tier 2: Add a subordinate clause
Tier 3: Add an example or result clause
Example (Band 7+):
Although many countries have implemented recycling programmes, the level of household participation remains low, which suggests that public awareness is still insufficient.
This uses:
- contrast clause
- result clause
- precise academic vocabulary
4. Common Errors That Keep Students Stuck at Band 6.5
1. Sentence fragments
Incorrect: Because people use cars more.
Correct: Because people use cars more, pollution levels have increased.
2. Overly long sentences
Avoid “monster sentences” with five or six clauses.
3. Misusing linking words
Never start a sentence with: Because of this reason (redundant).
Never write: Firstly is… (incorrect structure).
5. Band 9-Level Sample Paragraph Using Complex Sentences
Topic:
Some people argue that governments should invest more money in public transport rather than building new roads. To what extent do you agree or disagree?
Band 9 Sample:
Although expanding road networks may seem like a logical solution to traffic congestion, I strongly believe that governments should prioritise investment in public transport, as this approach offers long-term sustainability. Public transportation systems, which serve millions of commuters daily, can significantly reduce carbon emissions and ease urban congestion. Moreover, studies indicate that when reliable and affordable public transport is available, people are more willing to switch from private vehicles, thereby improving overall traffic flow. Therefore, by allocating resources to enhance public transit, governments can achieve both environmental and economic benefits.
6. Practice Exercises (Use These to Level Up)
Rewrite the ideas below into complex sentences:
- People work longer hours. Stress is increasing.
- Technology is improving. Many jobs are becoming automated.
- Online learning is convenient. Students sometimes lose motivation.
