A person immersed in mental work is extremely painful if he doesn't move his limbs often.

Heroism lies in sacrificing oneself for faith and truth.

Science is for the people.

Life is not a pleasure, but a very heavy job.

A mind without wisdom is like a lantern without a candle.

People are so used to using power to maintain order that it is impossible to consider social organizations that are not suppressed.

Pure and complete sadness is as impossible as pure and complete happiness.

The establishment of civilization is not a machine but an idea.

Successful teaching needs not compulsion, but arousing students' desire.

A teacher is a good teacher if he only has a passion for his career. If the love for education and the love for students are integrated, he is a perfect teacher.

The ideal book is the key to wisdom.

What matters is not the quantity of knowledge, but the quality of knowledge. Some people know a lot, but don't know the most useful things.

We not only live in this land today, but also live in the past and will live there forever.

No one can live forever, and nothing can last.

The value of life is not measured by time, but by depth.

I like the last sentence very much. The value of life is not measured by time, but by depth. The reason is that some people live to be a hundred years old, but in a hundred years, they are just doing what others have done for five or ten years. Some people only live to be twenty years old, but they have accomplished what others can't do in their lifetime! So a person's life is not how long you live, but what you do in your lifetime.

Challenge life in a limited time and do the most meaningful thing in life!