题干
If you buy ________ MP4 player in our store, you can get a watch for ________ free.
A：a; /
B： an; the
C：an; /
D：the; the
答案(点此获取答案解析）
C
If you buy ________ MP4 player in our store, you can get a watch for ________ free.
A：a; /
B： an; the
C：an; /
D：the; the
