The past is a mirror, but we often see only what we want to see.

永远不要停止学习；一旦停止，你就会过时。

在现代能源生产中，可持续性和效率必须齐头并进。

估计问题的性质不同。在这里，我们不关心检验特定的假设，而是关心估计参数的值。

I keep thinking about this river somewhere, with the water moving really fast. And these two people in the water, trying to hold onto each other, holding on as hard as they can, but in the end it’s just too much. The current’s too strong. They’ve got to let go, drift apart.