gnash

I'd rather have seen him gnash his teeth than smile so.

我宁可看他咬牙也不愿看这样的笑。

The wicked plot against the righteous and gnash their teeth at them;

恶人设谋害义人，又向他咬牙。

It makes me gnash my teeth to see so much food deliberately destroyed or wasted when there are people starving in Africa.

当非洲人民在 挨饿时，我看到这么多故意毁坏和浪费的食物，真 使我气得咬牙切齿。