difficult problem

基本解释

We will tackle this difficult problem.
我們將著手解決這個難題。
He soon turned his attention to the difficult problem.
他很快把注意力轉到這個難題上。
If a problem can be solved by money, it is not really a difficult problem.
如果一個問題可以用金錢得到解決，那麽它就不真是一個睏難的問題。

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.
不是所有人都是聰明人,這是個難題,大家能力不同,所以我們試圖營造一個環境,一個讓小投資者感到安全的環境,而無需憂心忡忡
耶魯公開課 - 金融市場課程節選
It shouldn't be difficult to see a kind of problem that is beginning to arise in Milton's text here.
這是一個很容易看出的問題,在彌爾頓的作品中也被提了出來。
耶魯公開課 - 彌爾頓課程節選

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