all ( ) can be done must be done.A.that B.which C.who D./如题,说明理由

合并句子all can be done.all must be done all that can be done has been done. 用what或者who合并句子all can be done.all must be done All can be done. All must be done.合并为一个句子怎么写? 为什么? all that can be done been done.why is all that?没有that不行吗? 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? _ can be done has been done.A.All B.All that C.All what D.Anything 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 All that can be done __been done.请问该用has还是 have? They won't leave until all that can be done is done The work can't_ all by himself.A、do b.did c.done d.be done They came to the conclusionn.________ by a computer.A.that not all things can be done B.because of not all things be doneC.being not all things can be done D.because not all things can be done it can be done 19.All that can be done .　　A.have been done B.have done C.has been done D.has done顺便,翻译一下这句话吧 all ( ) can be done must be done.A.that B.which C.who D./如题,说明理由 All that can be done___A.have been done B.have done C.has been done D.has done为什么选C怎么解释? All that can be done___________A.has done B.has been done C.have done D.have been done 请选入合适的选项.并解释原因,