"But we have an answer and we feel your pain." (Talking) Abdul Malik says Muslims face a modern challenge beyond shielding their young from traditional dangers like drugs and crime.

VOA: standard.2009.12.20

So in retrospect, I think the way to deal with crisis, deal with challenge, deal with difficult times, is like this: First, you need to be realistic.

回首去年，我们应对危机，面对挑战时，所采取的方法就是：,首先，要变得现实一些。

斯坦福公开课 - 百度CEO李彦宏演讲：全球最大搜索引擎的发展课程节选

And then we hand you 140,000 English words in the form of a big text file much like our aspiring pre-med students in recent months, and we challenge you to implement the fastest spellchecker possible.

然后我给你一个包含1万4千单词的超大文本,就跟前段时间那位,有抱负的医学预科班的学生一样,我想让你在最短时间内实现拼音检查。

哈佛公开课 - 计算机科学课程节选

The call is an apparent challenge to Israel, which has brought in thousands of additional police to prevent clashes like the ones that have broken out sporadically in the city during the past two weeks.

VOA: standard.2009.10.08

Sounds like a neat challenge.

听起来像个还不错的挑战。

麻省理工公开课 - 计算机科学及编程导论课程节选

"When you put that all together it suggest that we are going to need something like 50 percent more, perhaps 100 percent more, food from our existing land and that is a very significant challenge and we believe we need to be thinking seriously about that right away,"

VOA: standard.2009.10.21

Are you among those more comfortable, have you taken any computer science, were you programming at the age of 10 but you'd actually like to learn a bit about things you don't yet know and challenge yourself with new content or are you somewhere in between?

你对电脑比较熟悉么，你上过计算机专业方面的课程吗？,你是不是10岁就会编程,来上课的目的只是为了学习未知的知识,或者用新知识来挑战战自我？,还是二者兼有？

哈佛公开课 - 计算机科学课程节选