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

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And also for the challenge factor because they challenge the way I was thinking and writing

还有挑战因素，因为他们挑战了我思考和写作的方式，

怎么协调意见冲突 - SpeakingMax英语口语达人

When you think about your career, like a moment where you were particularly proud, or a moment where you were particularly challenged by something, and realized that makes me think in a wholly different way.

您在回顾您的工作时，比如说某一时刻您十分自豪，或者说您的观点受到了挑战,让您用一种,全新的角度来思考。

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