声音是由发声体的________而产生，人类是靠_________振动发声的。人耳听到的鼓声，是由_______的振动而产生。水中的鱼会被岸上的人的说话声吓跑，这是因为声音先经_________传播到水中，然后再经过__________传播而被鱼听到。

根据汉语提示、首字母或用所给词的正确形式完成句子。

1. I want to buy a teddy bear. But I don't have ________(足够的) money.

2. In our English Club I often ________(练习、操练)English with my friends.

3. Does this sentence _________ (听起来) right?

4. This pair of trousers is beatiful. I think it m_________ your sweater well.

5. Morning exercises are good for us. They help us get r___________ for the day.

6. Kitty is a t__________ student in our class and she has a healthy lifestyle.

7. It is 4.30. Millie __________ (write) a letter to her friend Danniel.

8. ________ (mango) and apples are my favourite fruit.