動詞 head off:

1. prevent the occurrence of; prevent from happening
   同義詞：debar, obviate, deflect, avert, stave off, fend off, avoid, ward off

1. The first thing to be done was to head off the enemy from the tender spots and vital places.
   首先要做的事是防止敵人從防守不嚴的部位及要害地方逃走。
2. I only asked you a question. There's no need to bite my head off.
   我只是問你一個問題。你何必對我這么兇。
3. He'll talk your head off if you give him a chance.
   他一有機會就會對你說個沒完。
4. Don't expect me to sit here like a good boy while Smith is up there talking his head off.
   不要指望我會像個乖孩子地坐在這兒，而史密斯在那里嘮叨個沒完。