His father had threatened disinheritance, but both men had known it was an empty threat.

他父亲威胁要剥夺他的继承权，但是两人都知道这是虚张声势。

《柯林斯英汉双解大词典》

But that may be an empty threat.

但这可能是个空洞的威胁。

youdao

One, that is an empty threat .

你这是威胁我不想当我的朋友？

youdao

Teachers and pupils both know that teachers cannot use force - and that parents would not tolerate the use of force - so an aggressive manner would soon be seen as an empty threat.

BBC: NEWS | UK | Education | Lesson discipline 'needs parents'

However, this is probably an empty threat.

ECONOMIST: European utilities: Bidding and competing | The

But this is an empty and dangerous threat.

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