Rewriting as Complex Sentences
Transforming simple or compound sentences into complex sentences is an essential skill for academic writing, competitive exams, and Std. 11–12 English board preparation. A complex sentence has one main clause and one or more subordinate clauses introduced by subordinating conjunctions or relative pronouns.
This post explains clear rules, examples, and practice exercises with answers.
1. What Is a Complex Sentence?
A complex sentence contains:One main clause (makes complete sense)One subordinate clause (depends on the main clause for full meaning)
Examples
I left the place because it was getting late.When the bell rang, students entered the class.
2. Types of Subordinate Clauses Used in Complex Sentences
A. Noun Clause
Functions as a subject, object, or complement.Introduced by: that, if, whether, wh-words
Example:
Simple: He said, “I am tired.”
Complex: He said that he was tired.
B. Adjective Clause
Describes a noun or pronoun.
Introduced by: who, whom, whose, which, that
Example:
Simple: I met a girl. She was very intelligent.
Complex: I met a girl who was very intelligent.
C. Adverb Clause
Shows time, reason, purpose, condition, concession, result, etc.
Introduced by: when, while, because, since, although, if, so that, before, after, till, unless
Example:
Simple: He worked hard to pass.
Complex: He worked hard so that he could pass.
3. Rules for Rewriting as Complex Sentences
Rule 1: Use subordinate conjunctions to show relationship
Convert phrases or short sentences using because, although, when, while, if, unless, before, after.
Simple: He finished the work early. He wanted to catch the bus.
Complex: He finished the work early because he wanted to catch the bus.
Rule 2: Replace nouns/pronouns with noun clauses
Simple: I know his address.
Complex: I know where he lives.
Rule 3: Use relative pronouns for adjective clauses
Simple: I saw the boy. He stole the purse.
Complex: I saw the boy who stole the purse.
Rule 4: Use participle phrases → subordinate clauses
Simple: Seeing the police, the thief ran away.
Complex: When he saw the police, the thief ran away.
Rule 5: Join ideas of cause, time, condition, purpose
Cause: because / since
Time: when / while / after / before
Condition: if / unless
Purpose: so that / in order that
Simple: I must leave now. I have to attend a meeting.
Complex: I must leave now because I have to attend a meeting.
4. Model Examples
1. Simple → Complex
Simple: She was tired. She went to sleep.
Complex: She went to sleep because she was tired.
2. Compound → Complex
Compound: Work hard and you will succeed.
Complex: If you work hard, you will succeed.
3. Phrase → Complex
Phrase: On reaching the station, he called me.
Complex: When he reached the station, he called me.
5. Practice Exercises
Rewrite the following as complex sentences:
1. He was late. He missed the train.
2. I saw a man. He was carrying a heavy load.
3. Finish your work. Then you can play.
4. He failed. He did not study well.
5. She is honest. Everyone admires her.
6. Open the window to get fresh air.
7. I heard the news. I was shocked.
8. Do your homework or you will be punished.
9. He worked hard. He wanted to win the prize.
10. The teacher praised the boy. He stood first in class.
Answer Key
1. He missed the train because he was late.
2. I saw a man who was carrying a heavy load.
3. You can play after you finish your work.
4. He failed because he did not study well.
5. Everyone admires her because she is honest.
6. Open the window so that you may get fresh air.
7. I was shocked when I heard the news.
8. You will be punished if you do not do your homework.
9. He worked hard so that he could win the prize.
10. The teacher praised the boy who stood first in class.
