Her dismissal came as a bolt from the blue.

她被解雇简直就是晴天霹雳。

《牛津词典》

But soon a bolt from the blue shocked him.

但很快一个晴天霹雳让他震惊。

youdao

A: What a bolt from the blue it is! My affectionate grandfather passed away yesterday.

A：真是一个晴天霹雳，我亲爱的祖父昨天去世了。

youdao

Maybe the concept came to you in a flash, the proverbial bolt out of the blue.

FORBES: You Have THE BIG IDEA, What Do You Do Next?

If, at the time of the Cuban missile crisis, for example, which you and I remember because we were around, it had all gone wrong and the Russians had put a bolt from the blue on London and Mr MacMillan was killed, the decision whether to launch the B-force, the B-bombers with their hydrogen bombs, would have gone to the Chief of Bomber Command, an airman in uniform.

BBC

But some say that it is absurd to depict the law lords' judgment as a bolt from the blue.

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