difficult problem

基本解释

We will tackle this difficult problem.
我们将着手解决这个难题。
He soon turned his attention to the difficult problem.
他很快把注意力转到这个难题上。
If a problem can be solved by money, it is not really a difficult problem.
如果一个问题可以用金钱得到解决，那么它就不真是一个困难的问题。

She began to explain to the students how to solve a very difficult problem.
It's a difficult problem that not everyone is smart -they vary in their ability -so we try to make a world in which it's pretty safe for the small investor who's not paying attention.
不是所有人都是聪明人,这是个难题,大家能力不同,所以我们试图营造一个环境,一个让小投资者感到安全的环境,而无需忧心忡忡
耶鲁公开课 - 金融市场课程节选
It shouldn't be difficult to see a kind of problem that is beginning to arise in Milton's text here.
这是一个很容易看出的问题,在弥尔顿的作品中也被提了出来。
耶鲁公开课 - 弥尔顿课程节选

Each one of these is a difficult problem to unwind, and many of us struggle with more than one.
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