Underline the relative clause in each sentence. Decide if the relative pronoun is the subject (S) or object (O) of the relative clause and if we can or cannot omit it.

1. The new vocabulary items which we learnt yesterday are difficult to remember.

2. I don't like the grammar exercises which are in this book.

3. The man who translated this novel into Vietnamese must be proficient in English.

4. The students who love languages can join our Reading Club.

5. The teacher who we admire can speak three languages.