Since then, balancing his solo career with movie projects has been his biggest challenge.

VOA: standard.2010.04.16

Then, the next challenge was to figure out how to keep the dots on the streets because they were going all over the place.

接下来的挑战是,想办法让这些点固定在,街上，因为,它们总是不停地移动。

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And the challenge then is, for us, if our goal is to become practical idealists is to understand what it is that brings about change and then do it.

困难在于，如果我们想成为实践理想主义者,就要理解是什么带来改变然后去做。

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