may have been和 must have been been是不是不仅表示被动?
在英语里coms been、must been和may been和come have been、must have be
must have been done是什么被动语态
could have been 和may have been 有什么区别?
关于must have been
MUST have been done
must have been
can't have been和must have been
A.must be B.may have been C.can have been D.could be ,为什么呢,
may not have been...与 may have not been ...
have been tired 被动么?
must have been doing与must have been done都表示推测,有什么区别呀?
may have been怎么用