1, Zhang Heng made outstanding contributions to China's scientific and cultural undertakings all his life and was one of the great scientists in ancient China. He is modest and prudent, diligent in learning, and shows meticulous, striving for perfection, fearless of power and enterprising academic style in his career. And his noble character of not seeking fame and fortune is worth learning.

Einstein once invited a friend to his home for dinner.

The meal is ready, but his friend hasn't come yet. Einstein looked at the food that was a little cold and turned to the laboratory to do experiments.

Just as Einstein was doing the experiment, his friend came. His friends didn't see him, so he ate up the rice and put the chicken bones in a box.

Einstein came out of the experiment and saw the box on the table and the upside-down plates and bowls. He patted his forehead and said, "Oh, dear! Look at my brain! I thought I didn't eat. "