种一棵树最好的时间是20年前，其次是现在。

We must always remember that behind every data point is a human life waiting for hope.

除非我们愿意为之而死，否则我们不能确定有值得为之而活的东西。

"The game is afoot."

I'm not a saint, I'm just a sinner who tries.

The truth of history is often found in its silences.

Learning consists in the modification of certain mediating processes which operate between the stimulus and the response.