Question

【题目】一Look! Someone _____________ room for us!

一I guess Mast did this. He's such a nice boy.

A. is cleaning.B. cleansC. has cleaned

Answer 1

【答案】C

【解析】

句意：——看！有人已经为我们打扫了房间！——我猜一定是Mast做的。他是个这么好的男孩。

is cleaning 现在进行时；cleans 一般现在时；has cleaned 现在完成时。根据“I guess Mast did this.”可知，房间已经打扫了，故用现在完成时，故选C。