实现明天的唯一限制将是我们今天的怀疑。

学历史,学历史。历史里藏着一切的智慧。

争论的焦点不是“煤炭 vs. 可再生能源”，而是转型期间如何整合两者。

I would like to fly in space.Absolutely.That would be cool.I used to just do personally risky things， but now I’ve got kids and responsibilities， so I can’t be my own test pilot.That wouldn’t be a good idea.But I definitely want to fly as soon as it’s a sensible thing to do.