13.( ) A. in the front of B. behind C. at front D. in front of
12.( ) A. old B. new C. useful D. good
11.( ) A. using B. use C. to use D. used
10.( ) A. For B. By C. In D. On
9.( ) A. seeing B. to see C. looking D. to look
8.( ) A. mustn't B. can't C. needn't D. shouldn't
7.( ) A. his own B. their own C. own his D. own their
6.( ) A. become B. will become C. turn D. will turn
5.( ) A. what B. when C. how D. where
4.( ) A. began B. has begun C. have begun D. will begin