must have been和must be的区别要口诀,简短,易懂.

must have been done must have done must have/ must have been的区别 must be和must have been有什么区别he must have been sleeping.为什么这里要用must have been而不用must be i think he must have been a mechanic,中的must和have been是什么词啊? 英语中,must have been 和 must have +过去分词,有什么区别如题 i must have watched 和 i must have been watch TV意思一样吗 为什么 MUST have been donemust have been doing must have been +名词must have done以上的区别还有是否有must have been done 的用法 和区别EG1 I must have been sleeping 2 your dress must have been expensive.3 I didn't hear the phone,I must have may have been和 must have been been是不是不仅表示被动? must have been与must have done的区别? must have been和must be的区别要口诀,简短,易懂. must be的用法和must have been的用法是什么? can't have been和can' have done有什么区别或者must have been和must hane done;may have been和may have done must not have been;could not have must have been和can't have been和现在完成时有没有联系啊 must have been done/must be done求解两者异同 can't have been和must have been每一个的用法 It Must Have Been Love (Cologne) 歌词 请问：有没有must have been?