车速越高，方向的操纵性越差，一旦遇到紧急情况，很难控制车辆的速度和方向。

The faster of the speed of a car, the harder of controlling directions, once urgent things happened, the speed and direction of cars are difficult to control.

youdao

如果有了这个账户，就意味着一旦诸如遇到车坏了、工作丢了或其他不可预见的紧急情况发生时就不必举债度日了。

If he has one, then it means that he won't have to go into debt when his car breaks down, he loses his job or some other unforeseeable emergency happens to him.

youdao

这就像一群朋友，平时大家聚在一起，看不出什么差别，可是一旦遇到了紧急情况，或出席正式的大场面，每个人临场的表现就完全不同了。

It is like a group of friends who are usually the same but each one's attitude to handling things are very different in urgent or formal grand occasion.

youdao