3. Smallpox, which once killed thousand of people every year, has disappeared.
4. I passed him a large glass of whisky which he drank immediately.
5. The small man, who/whom nobody recognise, was Lisa's husband.
6. This is Mr Jones, who writes poetry.
7. This is Felicity, whose sister you met last week
8. He swam across the English Channel, which is hard to believe.
Chúc bạn học giỏi!!!