根据句意用括号内所给词的适当形式填空。

1．He is often heard           (sing) in the next room.

2．English and French          (speak) in Canada.

3．Emma is terribly ill and she needs an             (operate) at once.

4．He killed his enemy and           (flee) from the country.

5．I’ve been trying to           (convince) him to see a doctor.

6．Germans likes         (music) who play different kinds of music.

7．Is the stamp used for         (post) a letter?

8．On my way home, I remembered that I           (not close) the windows of the classroom.

9．Cartoons are no          (long) just for kids.

10．All the friends are as         (friend) to him as before.