Question

The teacher_____have thought Johnson was worth it or she wouldn’t have wasted time on him,I suppose

1. A.
   should
2. B.
   can
3. C.
   would
4. D.
   must

Answer 1

D
“must have +动词+ed形式”表示“一定做了某事”。根据所提供的情景or she wouldn’t have wasted time on him可判断出老师一定认为Johnson值得教，要不她不会在他身上浪费那么多时间。“should have +动词+ed形式”表示“本来应该做某事，而没有做”，常用于表示责备。“can have +动词+ed形式”表示“可能做了某事”。would用于表示虚拟、假设、条件等，有“要、将要、会、就会”等意思。