This is a difficult problem to solve.

这是一个很难解决的问题。

youdao

We must arrive before ten o 'clock, this is a difficult problem.

我们必须十点钟以前到达，这是个难题。

youdao

I know this is a difficult problem, but do you prepare to face the challenge?

我知道这是个难题，但是你准备好迎接这个挑战了吗？

youdao

This is a difficult problem.

FORBES: Do the Interactions of Pharma With Medical Experts Compromise Health Guidelines?

Mr. ZOELLICK: This is a devil of a difficult problem.

NPR: U.S. Relationship with Sudan a Balancing Act

And they have a tremendous amount of capacity of resources to deal with this very difficult problem, but it is a crisis significant enough that a lot of countries, including the United States, led by the United States, have come in to offer further aid and assistance and expertise to help them deal with it.

WHITEHOUSE: Press Briefing