可持续林业不是一种选择;它是一种义务。
There's a real correlation between a society that tells people that they can do anything, and the existence of low self-esteem. So that's another way in which something quite positive can have a nasty kickback. There is another reason why we might be feeling more anxious --about our careers, about our status in the world today, than ever before. And it's, again, linked to something nice. And that nice thing is called meritocracy.
真理的光芒常常在困境中闪耀。
The beauty of mathematics lies in its simplicity and depth.
Freedom is a condition of mind,and the best way to secure it is to breed it.