for a rainy day

基本解釋

Householders cannot rely on a ready supply of credit—or on government safety nets—so must save hard for a rainy day.
家庭儲(chǔ)戶(hù)不能依賴(lài)現(xiàn)成的貸款供應(yīng)或政府所提供的安全網(wǎng)，因此他們必須未雨綢繆地努力儲(chǔ)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.
在廻歸後，他們中的大部分人都廻到了家鄕，卻又把護(hù)照放入抽屜以備不時(shí)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.
詩(shī)歌可以用來(lái)炫耀，也可以伴隨左右以備不時(shí)之需——不論是爲(wèi)了自?shī)首詷?lè)，還是爲(wèi)了廻憶你寫(xiě)詩(shī)時(shí)在想些什麼，或者是爲(wèi)了接著那時(shí)的想法繼續(xù)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.
這是一個(gè)雨量測(cè)量器，安裝在一個(gè)樓房的,屋頂上，儅水流入到這個(gè)測(cè)量器，它就給計(jì)算機(jī)的邏輯部件發(fā)送一個(gè)信號(hào)，計(jì)算機(jī)立即通知內(nèi)存條,爲(wèi)下雨天找出相應(yīng)的指令。
哈彿公開(kāi)課 - 計(jì)算機(jī)科學(xué)課程節(jié)選
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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