1.Can you tell me the reason _why____ you are so unhappy?
2.The boy ___whose__ father is a worker studies very hard.
3.This is the man _who____ wanted to see you.
4.This is the office ____where_ I work.
5.Sunday is the day ___when__ I am least busy.
6.The man to ____whom_ I nodded is Professor Li.
7.Is this the library from __which___ you borrow books?
8.This is the best film __that___ I have ever seen.