题目

Considering the time that has passed,the tired audience think the speaker must ____ most of the points he ought to ____.
A.mention; cover B.have mentioned; cover
C.mention; have covered D.have mentioned:have covered

提问时间：2021-01-08

答案

B.have mentioned; cover
must have + 过去分词 用以对已发生的事作以肯定推测
ought to 要接动词原形.如接have+ 过去分词便带有“（过去）本应该.”（而事实上没有.） 带有责备意味,这与语境不符