Doing it for yourself is good too, but you should do it for something that you really really want to happen, for really good reasons.

为自己而去做也是好的动机，但是需要是你非常非常希望做的，要有非常好的理由而去做。

youdao

I think if you do something and it turns out pretty good, then you should go do something else wonderful, not dwell on it for too long.

我认为如果你做某件事，然后结果是十分好的，那么你应该做其他更好的事，不要在那上面细想太长时间。

youdao

And when you do something good to others, you will feel happy, too.

当你做一些对他人的好，你会感到高兴了。

youdao

It's true there are dubious medical sites on the Internet, and you do best by following the same guidelines that serve well in the financial world: If something sounds too good to be true, it probably is.

CNN: Talk back to your doctor