根据句意和词首字母提示完成单词。

1. I hope you will r __1__ me from my photo.

2. Thanks for t __2__ me about what you like doing.

3. The girl is afraid o __3__ flying.

4. How do you f __4__ when you speak English?

5. —Where is Mike?

    —He has g __5__ to the library.

简述变风量空调系统的含义。