for a rainy day

基本解释

Householders cannot rely on a ready supply of credit—or on government safety nets—so must save hard for a rainy day.
家庭储户不能依赖现成的贷款供应或政府所提供的安全网，因此他们必须未雨绸缪地努力储蓄。
Many of those people have since returned to Hong Kong, their home, and have kept those second passports in the drawer for a rainy day.
在回归后，他们中的大部分人都回到了家乡，却又把护照放入抽屉以备不时之需。
It is something we can show off, or keep around for a rainy day to either entertain ourselves, work on, or reminisce what you were thinking that day when you wrote it.
诗歌可以用来炫耀，也可以伴随左右以备不时之需——不论是为了自娱自乐，还是为了回忆你写诗时在想些什么，或者是为了接着那时的想法继续思考。

He spoke for almost two hours on a cold and rainy day, without a hat or overcoat.
Now this is a rain gauge, and it's sitting on a roof of a building, and when the water falls into this gauge, it sends a signal to the logic unit of the computer, which immediately notifies the memory bank of the computer to seek out its instructions for a rainy day.
这是一个雨量测量器，安装在一个楼房的,屋顶上，当水流入到这个测量器，它就给计算机的逻辑部件发送一个信号，计算机立即通知内存条,为下雨天找出相应的指令。
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And making sure that folks have the opportunity and incentive to save for a home or college, for retirement or a rainy day is essential to that effort,".

It's very soothing and kind of introspective, and it's good for a rainy day.
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