根据中文提示填写单词，注意用适当的形式。

1. Students will send their homework to the teacher by _____ (电子邮件) in the future.

2. Yao Ming is good at _____ (打) basketball.

3. Lucy will _____ (到达) in Yiwu tomorrow morning.

4. We must speak English _____ (响亮) in class.

5. All the visitors from Australia are looking forward to _____ (参观) the Forbidden City.

6. Lucy plays table tennis well,but Betty plays it _____ (更好).

7. It's difficult for me _____ (说) English to a foreigner.

8. _____ (看) TV too much is bad for us.

9. These _____ (玩具) are so interesting.Many children like them very much.

10. I like listening to music in my _____ (自由的) time.

循环水系统中经常使用的含磷有机缓蚀阻垢剂，一般分为有机膦酸酯和有机膦酸盐两大类。