It is certain that we are able to reach the top of the mountain before night () 使用fall

问题描述:

It is certain that we are able to reach the top of the mountain before night () 使用fall

It's certain that we are able to reach the top of the moutain before night falls.
在黑夜降临前,未发生但是将会发生.用一般现在时falls表将来.