youdao

He began to work hard at it.

他开始为之努力。

youdao

She always works hard at it, you know.

你知道，她总是很努力。

youdao

And,being one of the older skaters at 27, it feels good to be here still competing hard and representing the U.S.

VOA: standard.2010.02.23

And it's not hard to see how the heat of reaction at room temperature can be related to they heat of reaction at other temperatures.

知道室温下的反应热,如何与其他温度下的反应,热联系起来这点并不困难。

麻省理工公开课 - 热力学与动力学课程节选

So it's actually really hard to find like a boyfriend or guys who are interested in you at NYU.

所以，要想在纽约大学找一个对你感兴趣的男朋友或男生，真的很困难。

在哥伦布环岛 - SpeakingMax英语口语达人

I've been working hard at it, but there's still lots of work to do.

WSJ: Jets' Sanchez, Smith not sharp early in QB battle

But I had to work very hard at it, and there's still complications from it today.

NPR: Confronting Misconceptions About Cancer Prevention

"Let's put it this way: I work very hard at it, " Heimlich told CNN.

CNN: An Experiment In Cincinnati