1. 那个男孩根本不懂礼貌。

2. 瞪着眼睛看人是不礼貌的。

3. 他走路的样子很不自然。(in a ．．． manner)

Key:

1. The boy has no manners at all.

2. It's bad manners to stare at people.

3. He is walking in a rather unnatural manner.