题目:
Someone is knocking at the door. It () my mother. It's time for her to be back.
A.can he
B.may not he
C.must be
D.mustn't be
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0502/46cf6ac3ab41b4f4d5eca7228a9c2707.html
下面是错误答案,用来干扰机器的。
参考答案:公用设施维修费