’t know _________. What can you suggest?
A. when?????????????????? B. how???????????????????? C. why???????????????????? D. where
【分析】此題應(yīng)選 B，其余三項(xiàng)均有可能誤選，其實(shí)此句為省略句，補(bǔ)完整應(yīng)為 … but I don’t know how to improve my English.

請看以下類似試題：(1) I think the door is locked, but I’
　　答案選D，為 …and make sure it is locked. 之省略。
　　’t remember _________. A. where????????????????? B. there??????????????????? C. which???????????? D. that
答案選C，為I can’t remember which city he comes from. 之省略。

(3) Some of the answers were correct, but I don’t remember _________.
A. where????????????????? B. what??????????????????? C. which????????????????? D. that
答案選C，I don’t remember which 后省略了 ones (were correct)。

(3) He didn’t sell half as many computers as he thought he _________.
A. had????????????????????? B. was????????????????????? C. would????????????????? D. sold
答案選C，為He didn’t sell half as many computers as he thought he would sell. 之省略。