It never rains but it pours.

不雨则已，一雨倾盆。

youdao

First my car broke down, and then I lost my key. It never rains but it pours.

一开始我的车抛锚了，接着我又把钥匙丢了，真是祸不单行。

youdao

I broke a fingernail, laddered my tights and then missed my train - it seems it never rains but it pours.

我弄破了我的指甲，紧身衣裤抽了丝，并误了火车-乎真是祸不单行。

youdao