It is that I can still remember was discussed at the meeting.A. sure; whenB. sure; whatC

问题补充：

It is that I can still remember was discussed at the meeting.

A. sure; when

B. sure; what

C. certain; when

D. certain; what

答案：

A. sure; when

B. sure; what

C. certain; when

(答案→)D. certain; what

解析：“我肯定记得大会上讨论过的事。”sure的主语必须是人，certain的主语可以是人和物，第二空从句缺主语所以用what，答案D。