用所给词的适当形式填空.

1. The polar bears are kind of        (aggress).

2. He was____    (surprise) to find no one in the zoo.

3. Zoos are like          (live) textbooks for young people.

4. He ________(use) to be a teacher.

5. How much do you           (weight)?

目的地是南美，非洲的船，所有人要“黄热病预防接种证书”；来自黄热病疫区的飞机要“灭蚊证书”；大型客车是登车检查。所有人要《入境检疫申明卡》，《国际旅行健康检查证明书》或《国际预防接种证书》( )