1. 根据语境从方框中选择恰当的单词填空，有的需要变换形式。

mail,   proper,   fix,   textbook,   lend

1. （1） The truck isn't working. There must be something wrong with it.
3. （2） This isn't my bike. Katehers to me just now.
5. （3） Don't throw this radio away. It can be.
7. （4） More and more people send and receive photos andon the Internet.
9. （5） Students are allowed to bring theirin the history exam.