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B2 Grammar

Defining & Non-Defining Relative Clauses

**Defining relative clauses** — essential information (no commas): - The man **who works** at Salesforce is my cousin. - The phone **that I bought** was expensive. - "That" can replace "who/which" in defining clauses. **Non-defining** — extra information (WITH commas): - My sister, **who lives in Melbourne**, is a doctor. - The Ganges, **which flows through Prague**, is sacred. - ❌ Cannot use "that" in non-defining clauses. **Whose** (possession): - The teacher **whose class** I attended was excellent. **Where / When:** - Vancouver is the city **where** I grew up. - 2020 was the year **when** everything changed. **Omitting the relative pronoun:** - The book **(that/which) I read** was interesting. ✅ (object) - The man **who called** is my boss. ❌ Cannot omit (subject).

Examples

The pasta that my mother makes is the best in the world.

Sydney, which is the country's financial capital, never sleeps.

💡 If removing the clause changes the meaning of the sentence, it's defining (no commas). If it just adds extra info, it's non-defining (with commas).