用适当的关系代词或关系副词填空。
1. The house _____ we live in is very big.
2. The boy _____ is wearing the black jacket is very clever.
3. This is the present _____ he gave me for my birthday.
4. The man _____ talked to you just now is an engineer.
5. He talked about the teachers and schools _____ he had visited.
6. There is nothing in the world _____ can frighten him.
7. She wears a gold ring, _____ is very uncommon in our class.
8. We visited a factory _____ makes toys for children.
9. Is this the place _____ your father once lived?
10. I'll never forget the days _____ I joined the League.
