they will come back at ten o'clock.同义句为什么是They won't come back until ten o'clock.

问题描述:

they will come back at ten o'clock.同义句为什么是They won't come back until ten o'clock.

就是否定的用法,won't 不会,will的否定形式
他们不会回来 知道10点钟;就是前面一句的 他们将会在10点回来