Question

Thinking that you know _________ in fact you don’t is a serious mistake.

1. A.
   what　
2. B.
   that　
3. C.
   when　
4. D.
   however

Answer 1

A
本题考查学生对主语从句和宾语从句的穿插理解。在that you know _________ in fact you don’t宾语从句中缺少一个能承前启后的联系；同时又作know和you don’t know的宾语,因此只有A项,what疑问代词最充分。