Why Complex Sentences Matter for IELTS
To achieve Band 7+, you need to demonstrate a "variety of complex structures" with "frequent error-free sentences." Complex sentences are essential for this score.
What Are Complex Sentences?
Complex sentences contain one independent clause (complete sentence) and one or more dependent clauses (incomplete ideas that depend on the main clause).
Simple Sentence
Community service helps teenagers.
One independent clause - Band 5-6
Compound Sentence
Community service helps teenagers, and it benefits local communities.
Two independent clauses - Band 6
Complex Sentence
Community service, which involves unpaid work, helps teenagers develop essential life skills.
Independent + dependent clause - Band 7+
Three Main Types of Complex Sentences for IELTS
| Type | Purpose | Example |
|---|---|---|
| Relative Clauses | Add extra information about nouns | Students who volunteer regularly develop strong work ethics. |
| Conditionals | Express hypothetical situations | If governments invested more, education would improve. |
| Passive Voice | Focus on action/result, not doer | Traditional skills are being replaced by technology. |
How Many Complex Sentences Do I Need?
For Band 7: Aim for 50-60% complex sentences (about 7-10 in a 270-word essay)
For Band 8: Aim for 70%+ complex sentences (about 12-15 in a 270-word essay)
Mix them throughout your essay - don't cluster them all in one paragraph!
Relative Clauses in Academic Writing
Relative clauses add essential or extra information about nouns. They begin with relative pronouns: who, which, that, where, whose
1. Defining Relative Clauses (Essential Information)
These clauses are necessary to identify which person/thing we're talking about. NO commas are used.
- Students who study regularly tend to perform better in exams.
- The benefits that community service provides are substantial.
- Countries where education is prioritized show higher economic growth.
2. Non-Defining Relative Clauses (Extra Information)
These clauses add bonus information that could be removed. USE commas to separate them.
- Technology, which has revolutionized communication, affects every aspect of modern life.
- My hometown, where I spent my childhood, has changed dramatically.
- Online education, which became popular during COVID-19, offers flexibility.
Wrong: Technology, that has revolutionized communication, affects modern life.
Right: Technology, which has revolutionized communication, affects modern life.
3. When to Use Each Relative Pronoun
| Pronoun | Use For | Example |
|---|---|---|
| who | People | Teachers who inspire students make a lasting impact. |
| which | Things/Animals | Skills which are learned early become automatic. |
| that | People/Things (defining only) | The approach that works best depends on context. |
| where | Places | Cities where pollution is high face health challenges. |
| whose | Possession | Students whose parents are supportive often succeed. |
Practice: Combining Sentences
Combine these simple sentences using relative clauses:
1. Many students fail exams. These students don't prepare adequately.
2. Social media has changed communication. Social media was invented in the 2000s.
Conditional Structures for IELTS Writing
Conditionals express hypothetical situations and are particularly useful for problem-solution essays and when proposing solutions or discussing possibilities.
1. First Conditional - Real Future Possibilities
Form: If + present simple, will + base verb
Use: Things that are likely to happen
- If governments invest in education, future generations will benefit.
- Students will perform better if they receive adequate support.
- If this trend continues, environmental problems will worsen.
2. Second Conditional - Unreal Present/Future
Form: If + past simple, would + base verb
Use: Imaginary or unlikely situations in present/future
- If tuition fees were lower, more students would attend university.
- We would see improvements if governments prioritized healthcare.
- If people had more leisure time, they would pursue hobbies.
3. Third Conditional - Unreal Past
Form: If + past perfect, would have + past participle
Use: Imaginary situations in the past (less common in IELTS)
- If earlier generations had protected the environment, we would not face these problems today.
- Education systems would have evolved differently if technology had been available sooner.
4. Mixed Conditionals
Combine different times - past action with present result
- If governments had invested in infrastructure, cities would be better equipped today.
- If we had addressed climate change earlier, the situation would not be so critical now.
5. Zero Conditional - General Truths
Form: If + present simple, present simple
Use: Scientific facts or things that are always true
- If students receive encouragement, they perform better.
- If people exercise regularly, they experience health benefits.
Alternative Forms (More Advanced)
Instead of starting with "If," use these for variety:
- Were governments to invest in education, results would improve. (formal inversion)
- Should funding increase, more programs could be implemented.
- Had previous policies been effective, we would not face these challenges.
- Unless action is taken, the problem will worsen. (= If action is not taken)
Practice: Choose the Correct Conditional
1. If technology (continue) to advance, traditional jobs will disappear.
2. If governments (reduce) working hours, people would have better work-life balance.
3. If previous generations (address) climate change, we would not face this crisis.
Passive Voice in Academic Writing
The passive voice is common in academic writing when the action or result is more important than who does it. However, don't overuse it - IELTS values natural, varied writing.
When to Use Passive Voice
1. Action is More Important
Traditional skills are being replaced by modern technology.
(Focus on what's happening, not who's doing it)
2. Doer is Unknown/Unimportant
The policy was implemented in 2015.
(We don't know or care who implemented it)
3. Doer is Obvious
English is spoken in many countries worldwide.
(Obviously by people - no need to state)
Passive Voice Forms by Tense
| Tense | Active | Passive |
|---|---|---|
| Present Simple | Technology affects education. | Education is affected by technology. |
| Present Continuous | Technology is changing education. | Education is being changed by technology. |
| Present Perfect | Technology has transformed education. | Education has been transformed by technology. |
| Past Simple | The government introduced new policies. | New policies were introduced by the government. |
| Future Simple | AI will replace many jobs. | Many jobs will be replaced by AI. |
| Modal Verbs | We should address this issue. | This issue should be addressed. |
Common IELTS Passive Structures
Problem Statements:
- This problem is caused by several factors.
- Environmental damage is being accelerated by human activities.
- Traditional values are being eroded by modern lifestyles.
Solutions:
- This issue could be addressed through education.
- Resources should be allocated more effectively.
- Measures need to be taken to prevent further damage.
General Statements:
- It is widely believed that education is important.
- It has been argued that technology improves quality of life.
- It is generally accepted that exercise benefits health.
Active vs. Passive - Which is Better?
For each scenario, choose the better version:
1. Discussing a problem in your essay:
2. Expressing your opinion:
Interactive Sentence Combiner Tool
Practice combining simple sentences into complex ones. Select sentence parts and choose how to connect them.
Exercise 1: Relative Clause Builder
Combine these sentences using a relative clause:
Sentence B: These students balance work and study.
Step 1: Choose the relative pronoun:
Step 2: Your combined sentence:
Exercise 2: Conditional Builder
Build a conditional sentence:
Result: Traffic congestion decreases
Step 1: Choose conditional type:
Step 2: Your conditional sentence:
Common Grammar Errors to Avoid
Even advanced students make these mistakes. Learn to spot and correct them!
Error 1: Missing Commas in Non-Defining Relative Clauses
If the clause adds extra information (could be removed), use commas!
Error 2: Using "That" in Non-Defining Relative Clauses
Never use "that" with commas. Use "which" for non-defining clauses.
Error 3: Wrong Conditional Forms
Don't use "will" in the if-clause of first conditionals!
Error 4: Passive Voice with Wrong Form
Passive = be + past participle (solved, not solve)
Error 5: Subject-Verb Agreement in Relative Clauses
The verb agrees with "students" (plural), not "who"!
Error 6: Overusing Passive Voice
Too much passive makes writing boring! Mix active and passive naturally.
Error Correction Game
Find and correct the error in each sentence:
1. Students which work part-time often face challenges.
2. If governments will prioritize education, society would benefit.
3. The problem can be solve through better education.
Comprehensive Practice Quiz
Test your understanding of all complex sentence types covered in this lesson.
Question 1: Choose the sentence with the correct relative clause:
Question 2: Which conditional is appropriate for this situation: "I want to discuss a realistic future possibility"?
Question 3: Choose the best passive structure:
Question 4: Which sentence correctly uses a non-defining relative clause?
Question 5: Choose the sentence with correct conditional form:
Next Steps:
1. Practice incorporating these structures in your essay writing
2. Aim for 7-10 complex sentences per essay (out of about 13-15 total sentences)
3. Always prioritize accuracy over complexity
4. Mix different types - don't use only relative clauses or only conditionals
5. Continue to Lesson 13 to learn about cohesion and coherence