题目内容：

It is -- that people will not agree with what the manager said at the meeting
It is ----- that people will not agree with what the manager said at the meeting.
A、sure
B、certain

优质解答

certain
在“It is…that结构中只能用certain,不能用sure.
sure与certain虽可换用,但隐含意思不同.Sure表示主观的推测或感觉,所述事实并不一定如此.certain则指说话者有充分的理由或根据,肯定某事会发生.