在下面对话的空白处填入适当的话语(话语可以是句子、短语或词)，使对话完整。
A: Hey, Ginny. What do you call those big, gray things in the water?
B: 1______.
A: What?
B: Manatees. They're very gentle and very shy.
A: 2______?
B: They're usually about 10 feet long and they weigh about 1000 pounds.
A: How much do they need everyday?
B: They need about 1 00 pounds of aquatic food a day.
A: 3______?
B: It is underwater plants and vegetation (植被).
A: That's what they eat?
B: Yes. it is.
A: 4______?
B: Yes, they are endangered (陷入困境). But, we're trying to save them.
A: Wait a moment. Why are they endangered?
B: 5______.
A: Where do they live?
B: They live in the swamps (沼泽). 6______.They are endangered also because there sometimes
isn't enough food for all of them.
A: 7______. There used to be a lot of manatees, but now there aren't very many ofthem left, I think.
B: Yes, 8______. At this point, there are only about 2,500 in the U.S.
A: 9______?
B: Since 1927 laws have been passed to protect them.
A: Thank you for your information.
B: 10______.
1. They're called manatees／We call them manatees／They are manatees／Manatees
2. How big are manatees／they
3. What do they eat
4. Are manatees／they endangered
5. Because their homes are disappearing／Because their living areas are populated／
Because there is not enough food for them to eat
6. And they have become polluted
7. I am sorry to hear that ／What a pity
8. you are right／that's right
9. Have long have laws been passed to protect them／Are there any laws to protect them?
10. My pleasure
(答案不唯一)