Ⅰ. 用适当的“介词+关系代词”填空
1. America is the country in which George Washington was born.
2. The reason for which he refused to go to the party was that they hadn’t invited him to.
3. The person to whom I sent an e-mail never answers me.
4. The factory in which I work is a large one.
5. I have never heard of the singer about whom my son talks.
6. This is the man from whom I learned a lot in my life.
7. Wang Hong, with whom I went to the concert, enjoyed herself very much.
8. John invited about 40 people to his wedding, most of whom are family members.
9. He wrote a lot of novels, none of which were popular.
10. He was educated at a local high school, after which he went on to Beijing University.