"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

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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