"Our challenge now is to finish the job." He acknowledged the toughest part of the process may lie ahead;

VOA: standard.2009.12.25

Now for the hacker edition, if you are feeling up to a bit more of a challenge you'll find that when you run the game, one it's not all that hard to use some ASCII art just make it a little fancier as the teaching fellow who implemented this solution did.

对于升级版，如果你能应付更大的,挑战，你会发现当你在玩这个游戏时，用一些字符画把它做得,比那些教学人员做的更有新意,并不是那么困难。

哈佛公开课 - 计算机科学课程节选

That's a very difficult challenge in the Senate right now. It's not looking very good these days,

目前这在参议院是很大的挑战。现今的形势看上去不容乐观。

对全球变暖的政策 - SpeakingMax英语口语达人

Mr.Ban said there is a "huge challenge" in conducting a runoff election only 18 days from now.

VOA: standard.2009.10.20

We are living in very unusual times and I am sure that Ben Bernanke and other central bank presidents are losing sleep right now because this is a time to challenge monetary policy makers.

我们现在正生活在一个非常特殊的时期,并且我很肯定本？伯南克,和其他中央银行行长们,正在日夜担忧，因为,现如今是一个挑战货币政策制定者的时代。

耶鲁公开课 - 金融市场课程节选

With those legal and regulatory frameworks in place, President Sirleaf says the challenge now is making sure that they continue to be implemented properly.

VOA: standard.2009.08.14

So my challenge to you, and I know Professor Guttag can do this, my challenge to you is, a year from now, come back and look at code you wrote here.

因此我这里有个具有挑战性的任务，我知道Guttag也可能会说这个任务，我的这个任务就是，一年以后，回头来看,你之前写过的代码。

麻省理工公开课 - 计算机科学及编程导论课程节选

"This is the challenge we have now: to open a lot of those doors."

VOA: standard.2009.08.15

Now the challenge is not just to get the DNA that encodes a gene into a cell, the challenge is to get it into the cell in a form where the cell can use it, can express it and make proteins from it.

现在的问题不仅在于,要将编码基因的DNA转进细胞,还要让它进入细胞之后,能够为细胞所用,能够表达并合成蛋白质

耶鲁公开课 - 生物医学工程探索课程节选

That is our basic challenge now,". Geithner says it will take some time to bring down unemployment levels, which in October reached a 26-year high in the United States.

VOA: standard.2009.11.12

"The challenge now is to continue to show this clear and convening leadership, while not losing sight of your ongoing work to secure the security, prosperity and dignity of our fellow human beings."

VOA: standard.2010.07.06

"The challenge right now is that our emergency pre-positioned supplies were running quite low because the response in West Java was in progress still and that quake had just happened a few weeks ago,"

VOA: standard.2009.10.01

The effort has been to squeeze the Taliban out of certain areas and the challenge now is to hold those areas and maintain dominance of those areas that is surely what the whole operation has been, has been all about,".

VOA: standard.2009.07.27