1.Spelling Bee is a contest _____ competitors, usually children, are asked to spell as many words as possible.
A. which B. where C. what D. when
2. A housing bubble is an economic situation _____ occurs when house prices rise much too fast.
A. which B. where C. what D. why
3. —My key is gone. Have you seen it anywhere?
—Oh, it is in the room we had a talk last night.
A. that B. which C. where D. what
4.At present, we are studying a total of nine subjects, ________ I think is physics.
A. of them the most difficult B. and the most difficult of which
C. the most difficult of them D. the most difficult of which
5.Gun control is a subject _______ Americans have argued for a long time.
A. of which B. with which C. about which D. into which
6.Don’t talk about such things ______you are not sure of, ______ is what you should keep in mind.
A. as; which B. as; that C. that; as D. what; where
