Has everything can be done ? A. what; done B. that; been done C. that; already d

Has everything _____ can be done ______?

　 A. what; done　 B. that; been done

　 C. that; already done 　 D. what; already being done

试题答案

B

主句是现在完成时态，主句中有一个定语从句。