This is a hard one to explain. But I'll try.

这是一个比较难解释的东西，但我还是尝试去解释一下。

youdao

But the road to the White House is still a hard one.

但是通往白宫之路依然充满艰辛。

youdao

By any measure, the current decade is a hard one too.

不管以什么标准来衡量，现在的十年也是很困难的。

youdao

Push hard and fast. Aim for a rate of about one hundred compressions each minute.

VOA: special.2009.06.09

If the goal is to improve education, then one has to ask hard questions Like does a technology actually help?

假如目标是提高教育，那就要问问这样的问题,技术真的有帮助吗？

麻省理工公开课 - 媒体、教育、市场课程节选

It's hard to describe such a big neighborhood in one sentence.

我很难用一句话来描述这么大的一个社区。

布朗克斯的景点 - SpeakingMax英语口语达人

But in the meantime the spirit of new beginnings is a hard one to temper.

BBC: Tunisia��s vanguard hotels

This is a hard one to call, since it's a local derby where anything can happen.

BBC: SPORT | Northern Ireland | The Championship | Judge Jarlath: Who will make it?

Mr Osborne's budget puts Britain on the path to fiscal redemption, but that path is a hard one.

ECONOMIST: Britain's emergency budget