Difficult circumstances serve as a textbook of life for people.

I have noticed that youngsters given to the climbing habit usually do something when they grow up.

The reward of seeing the joy on the faces of the parents is immense.

The only limit is the one you set for yourself.

The office of President is one which requires the utmost diligence and attention.

物理学的美丽在于它能够用几个简单的方程来描述宇宙。

文学是一次旅行，一次对未知的探索，一次对真理的追寻。