Sustainability isn't just about planting trees; it's about planting the right trees in the right places for the right reasons.

A proof tells us where to concentrate our doubts.

The quality of institutions is the key determinant of a country's success or failure.

The intellectually sophisticated person is indifferent to all genuine individuality, because relationships and reactions result from it which cannot be exhausted with logical operations.

站在路中间是很危险的，因为你会被从两个方向来的车辆撞倒。