"Being more socially engaged in your community - maybe in environments which aren't always just the same, a little bit more challenging socially - may be a very good thing.

VOA: standard.2010.07.14

We're still close enough to the summer that the air is not just filling us up with extra static electricity, so it's a little more challenging here.

我们现在离夏天更近了,这样空气中不总是,充满额外的静电，所以这时做实验,会有一些挑战性。

麻省理工公开课 - 化学原理课程节选

I think this is as good list so let's go and think about what might be a little bit more challenging.

我想上面这些都是很好的例子,接下来我们思考一些更有挑战的问题

耶鲁公开课 - 生物医学工程探索课程节选

We're going to really get into this next class, but I just want to introduce it to you to give us a start, and many of you have used Lewis structures in high school, but we'll be doing some much more challenging Lewis structures, I can assure you, in this class here.

其实我们下节课才会详细介绍它，但是今天我只想以简单介绍作为开始，大部分同学在高中就用过路易斯结构了，但是我们会遇到一些更具挑战性的,路易斯结构，我可以向大家保证，在这门课中会的。

麻省理工公开课 - 化学原理课程节选

Cultural access is perhaps even more challenging.

文化接触可能更有挑战性。

麻省理工公开课 - 媒体、教育、市场课程节选

Well, crossword puzzles aren't a very deep subject, and we might wonder whether or not we would do better if we were engaged in something more mentally challenging than that.

填字游戏不算很深奥的东西，我们也不知道自己能否做得更好,如果我们去做,比填字游戏更富挑战性的事情。

耶鲁公开课 - 死亡课程节选

We differ from lower animals and our brains, which are much more capable of storing and processing information, but we're living in a time of revolution when machines are challenging or competing with our brains.

我们不同于其他低等动物，我们的大脑更能够存储和处理信息，不过身处改革年代,机器开始挑战甚至是,和我们的大脑开始竞争。

耶鲁公开课 - 金融市场课程节选