1. Last year we went to the farm ____which my father once worked.

2. In front of my house, there is a tree, ____ which some birds are singing.

3. He’s the model ____ whom we should learn.

4. The problem ____ which you argued just now has been solved.

5. Is this the car ____ which you paid much money?

6. In the dark street, there wasn’t a single person ____ whom she could turn for help.

7. The factory ____ which I work is far from my hometown.