用括号内所给单词的适当形式填空。1．Wemust

问题详情：

用括号内所给单词的适当形式填空。

1．We must ________ (help)Paul and Alan.

2. ________ (ask)Cindy for the book.

3．—Are these keys ________ (you)?

—No，they aren't.

4．Please e－mail ________ (I)at .

5．The girl's bag is ________ (lose)．

【回答】

　　s　　

知识点：构词法

题型：完成句子