need have done .本人才疏學(xué)淺,沒見過這種說法,通常是need to be done,表示需要被完成.如：All the housework needs to be done today.(今天需要完成所有家務(wù).)
must have done肯定猜測語氣,表示一定已經(jīng)完成了.如：He must have finished the housework.（他肯定已經(jīng)完成家務(wù)了.）
could have done 表示本可能已經(jīng)完成某件事,常表示結(jié)果與事實(shí)相反.can have done 不常見.如：He could have finished the housework if he didn't watch the basketball games.（如果他不看籃球賽,本應(yīng)該已完成家務(wù)了.）
should have done,應(yīng)該已經(jīng)完成某事,這個(gè)“應(yīng)該”不是指推測,而是指理論上的,或義務(wù)上的.如：According to the cookbook,the cake should have been baked well now.(根據(jù)菜譜,蛋糕應(yīng)該已經(jīng)被烤好了.)