It's not his problem. We ought to study hard.

不是他的问题，我们应该努力学习了。

youdao

His real name was Theodore. And if there was ever a problem she could not handle, her husband put things right.

VOA: special.2009.05.04

for it was not the old man who was a problem for me, but his Evil Eye.

VOA: special.2009.05.16

Imagine a swimmer in water over his head You are in deep water when you are facing a problem that you do not have the ability to solve.

VOA: special.2009.05.10

But whether or not his problem is an illness or something else remains an open question.

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One of Mr Gertz's difficulties is that solving crime is not his problem.

ECONOMIST: Mexico

That ended up not being his only problem.

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