根据汉语提示填空。

1. He didn't pass the exam. He looks ______ (不高兴).

2. "Gardon" is an ______ (不正确) spelling. It must be"garden"

3. It's not good to be an ______ (不诚实) boy.

4. He broke his leg yesterday. He is ______ (不能) to take part in the sports meeting.

5. Nothing is ______ (不可能) if we put our hearts into it.

6. He thinks it ______ (没有必要) to brush the teeth twice a day.