Here are the sentences filled in with the appropriate relative pronouns:

1. Stop him. He’s the man **who** stole my wallet.
2. There are many people **who** are living in very poor conditions.
3. I’ve ever read the book **that** Huong gave me yesterday.
4. The man **whom** I saw last weekend said something totally different.
5. They have invented a television set **that** is as small as a watch.
6. This is the building **that** was destroyed badly in the fire last night.
7. I’m talking about Tom, **who** is really friendly.
8. The boy **whose** sister is in my class can speak Japanese and Korean languages.