Once he made up his mind to do something, there was no stopping him.

他一旦下定决心做什么事，没有什么可以阻止他。

《柯林斯英汉双解大词典》

It's not hard to get him talking—the problem is stopping him!

让他谈话并不难—难的是让他住口！

《牛津词典》

Once let this fellow start talking, there was no stopping him. He talked like a book too, not like a human being.

一旦让这个家伙谈起来，谁也不能让他停下来。他说起话来就像本书根本不像个人。

youdao

By day and night,never stopping, biting at his nose, biting at his feet, the wolves stayed with him until the end.

VOA: special.2010.02.27

You're stopping him on his track when he says that he's going to marry her, and you say,

当你哥哥说打算跟这个女孩结婚时，你决定要阻止他这样错下去，于是你说，

The thing is 课堂 - SpeakingMax英语口语达人

His scam was easy enough for me to figure out, but no one was stopping him.

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But his voice is deep enough that he must be evil and stopping him must be very important.

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Once the good professor works up a good rant there is no stopping him except with facts, history, and reason.

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