Has all that can be done been done?为什么用HAS 不用 HAVE但是PEOPLE也是整体，动词用复数

all that can be done has been done. all that can be done has been done.中的that为all that can be done has been done.中的that为什么不能用which替换? all that can be eaten___eaten up答案是has been all为什么后面是单数? all that can be done has been done为什么用HAS all that can be done has been done 为什么要用has,不用have _ can be done has been done.A.All B.All that C.All what D.Anything 一个题 英语语法All that can be eaten_____eaten up.A.have beenB.has been理由 All that can be done __been done.请问该用has还是 have? Everything _____ has been doneA.which we must doB.all that can be doneC.can be doneD.that can be done选哪个?为什么? Has all that can be done been done?为什么用HAS 不用 HAVE但是PEOPLE也是整体，动词用复数 All that can be done__________.A.has been done B.has doneC.have been doneD.have done Has all that can be done been done?为什么用HAS 不用 HAVE PEOPLE也是整体,动词用复数先换成陈述句＝all that can be done has been done主语＝all 定语＝that can be done谓语＝has been done（被动）转换成简单的主句 all 作名词时后面的谓语动词什么时候用单数,什么时候用复数?例：All can be done (have/has) been doneAll that can be eaten (have/has) been eaten1L 我不是那个意思，是选has 还是have It is said that all which can be done has been done.这个句子哪里错了 All that can be eaten _______ eaten up. A are being B has been C had been D have been All that can be eaten( )eaten upA are beingB has been C had beenD have been选哪个为什么? be all that one can be开开开 美国陆军征募标语be all that you can be是什么意思