He said the crux of the matter was economic policy.

他说该问题的症结在于经济政策。

《柯林斯英汉双解大词典》

Now we come to the crux of the matter.

现在我们来谈问题的症结。

《牛津词典》

This is the crux of the matter.

这就是问题的关键所在。

《新英汉大辞典》