1. Did you recognize the woman who came into the room?

2. His friends congratulated him on passing the final examination.

3. If you spoke English naturally, they’d understand you.

4. Despite not having enough money, he decided to hold a party. 

5. Her book which became a best seller was published last year.

6. The man whom you met at the party last night is a famous actor.

1) A woman came into the room. Did you recognize her ?

=> Did you recognize the woman who came into the room ?

2) He passed the exam.

=> His friends congratulated him on his passing the exam.

3) They don't understand you, because you speak English unnaturally.

=> If you spoke English naturally, they’d understand you.

4) Though he didn't have enough money, he decided to hold a party.

=> Despite not having enough money, he decided to hold a party.

5)Her book was published last month. It became a best seller.

=> Her book which became a best seller was published last year.

6) The man is a famous actor. You met him at the party lastt night.

=> The man whom you met at the party last night is a famous actor.