1. Smoke from factories is polluting the air, …………….. rain forests can’t clean fast enough. A. in which B. where C. that D. which 2. In this restaurant I met the waiters, ………………. are college student. A. several of who B. several of whom C. several of which D. several of tha 3. This is his wife and children in …………….. he often takes pride. A. whom B. which C. that D. who 4. We all thank him ……………… gave us a lot of help. A. whom B. whose C. who D. which 5. The woman ……………….. I was looking smiled. A. at whose B. for whom C. at whom D. at which 6. Love, ……………… is a wonderful feeling, comes to everyone at some time in his life. A. that B. when C. where D. which 7. Is this the article ……………… you were interested? A. which B. in which C. at which D. who 9. The farmer and their cattle ……………… had been trapped in the storm were fortunately reused A. who B. whom C. which D. that 10. This is a letter ……………… I am looking forward during this morning A. in whom B. about whom C. to which D. about which 11. I don’t know the reason ………………. She hasn’t talk to me recently. A. on which B. for which C. of which D. about which 12. That’s the girl to …………….. my brother got engaged. A. which B. who C. whom D. that 13. The music ……………… we are listening to is very wonderful. A. to which B. which C. with which D. who