大学英语六遥考试词汇笔记(4)　　大学英语六遥考试词汇笔记 　　51.
He must have had an accident, or he _A_ then.
　　A would have been here B had to be here C should be here D would be here 　　must have + 过去分词 表示对过去行为的肯定推测; 　　与过去事态相反用：情态动词 + have + 过去分词 来体现虚拟语气; 　　must 一定，必须; neednt, dont have to 不必; 　　53.
You _A_ all those calculations!
We have a computer to do that sort of thing.
　　A neednt have done B must not have done 　　C shouldnt have done D can not have done 　　should have + 过去分词 本应该，本应当; shouldnt have done本不应该，本不应当; 　　44.
It was very kind of you to do the washing-up, but you _D_ it.
　　A mustnt have done B wouldnt have done 　　C mightnt have done D didnt have to do 　　52.
It was essential that the applications forms _C_ back before the deadline.
　　A must be sent B would be sent C be sent D were sent 　　It be essential that 后面一定用虚拟语气，且句子谓语动词固定为 + 动词原型; 　　It was essential that the applications forms send back before the deadline.
　　53.
We _D_ our breakfast when an old man came to the door.
　　A just have had B have just had C just had D had just had 　　when 还可以表示①刚.
.
就 、②恰在此时; 　　44.
I had just started back for the house to change my clothes _D_ I heard voices.
　　A as B while C after D when 　　45.
I felt somewhat disappointed and was about to leave, _C_ something occurred which attracted my attention.
　　A unless B until C when D while 　　64.
It was essential that these application forms _D_ back as early as possible.
　　A must be sent B will be sent C are sent D be sent