When hitchhiking， look like the person you want to pick you up.

The Government of the United States is a definite Government, confined to specified objects. It is not like the state governments, whose powers are more general.

The family is the basic unit of society, and it is under attack.

数学的力量来自于它的抽象和概括能力，将具体问题转化为普遍真理。

Music is the one art form that can express the inexpressible.