用所给单词的适当形式填空。

1.Every year, many ________ (tour) go to Zhalong to watch birds.

2.—Is drawing as difficult as swimming ? 

  —No, it's much ________ (easy), I think.

3.The children always enjoy ________ (they) at the weekend.

4.Speak louder, please. I can't hear you ________ (clear).

5.Tigers are ________ (protect) animals. We can't hunt them .