China _____ a sharp increase in the number of Social Networking Services users in the past years.
| A．has seen |
| B．saw |
| C．sees |
| D．was seen |
You can only be sure of __________ you have at present; you cannot be sure of something __________ you might get in the future.
| A．that; what | B．what; / | C．which; that | D．/; that |
A warm thought suddenly came to me __________ I might use the pocket money to buy some flowers for my mother’s birthday.
| A．if | B．when | C．that | D．which |
These shoes look very good. I wonder __________.
| A．how much cost they are | B．how much do theycost | C．how much they cost | D．how much are they cost |
—What did your parents think about your decision?—They always let me do __________ I think I should.
| A．when | B．that | C．how | D．what |
—It’s thirty years since we last met.—But I still remember the story, believe it or not, __________ we got lost on a rainy night.
| A．which | B．that | C．what | D．when |