Definition / Explanation
Defining relative clauses give essential information about a person or thing. They tell us exactly which one we mean, so without them the sentence would lose important meaning. At this level, the main relative words are who, which, and that, and sometimes the pronoun can be omitted. These clauses are common because they let us combine two shorter ideas into one clearer sentence. They are called defining because they identify the noun, not just add extra detail.
Key Rules
- Use who for people: the woman who called.
- Use which for things: the car which broke down.
- Use that for people or things in many everyday sentences.
- You can sometimes omit the relative pronoun when it is the object: the book (that) I bought.
- Do not use commas in defining relative clauses.
Examples
- The person who called you is here.
- This is the book that I told you about.
- The app which we use is free.
- The man I met yesterday works in finance.
- I need a laptop that runs this software.
Common Mistakes
- ❌ My brother, who lives next door is a doctor. -> ✅ My brother who lives next door is a doctor.
- ❌ This is the book what I bought. -> ✅ This is the book that I bought.
- ❌ The woman which called me was polite. -> ✅ The woman who called me was polite.