翻译At one time Einstein （爱因斯坦）travelled all over

he United States giving lectures（做演讲）. He travelled by car and soon became quite friendly with his driver. The driver listened to Einstein's lecture again and again. One day, he said to Einstein, "I can remember your lecture so well that I can give it myself." Einstein smiled and said, "Why don't you give the lecture for me next time? I'll be the driver." The driver agreed.
That evening both of them went to the lecture hall. Nobody there had seen Einstein before. When the driver stood on the stage（舞台）, everybody clapped . Then he began the lecture and didn't make a single（一个） mistake. It was a great success. When it was over, people clapped and clapped. Then he started to leave, shaking hands with everybody. Einstein followed him quietly.
Just before they got to the door, a man asked the driver a very difficult question. The driver listened carefully. He didn't understand a thing but nodded （点头）his head as if (好像) he did. When the man stopped talking, the driver said, "I think this question is very interesting, but really quite easy. To show how easy it is, I would like to ask my driver to answer it."

爱因斯塔在美国做演讲，他坐着汽车到处旅行，不久就和他的司机相处得很好，司机一场又一场的听了爱因斯坦的演讲。一天，他对爱因斯坦说“我能把你的演讲都记住了，因此我可以自己来演讲了”爱因斯坦笑了，说“下一次为什么不由你来演讲呢？我做司机”司机同意了。那天晚上，他们去了演讲大厅。在那里以前没有人见过爱因斯坦。当司机站到舞台上，人们鼓掌。然后他开始演讲，一个字都没有错。演讲很成功。演讲结束后，人们连续的鼓掌。然后他开始离开，同每一个人握手，爱因斯坦静静的跟着他。在他们快到大门口的时候，一个人问司机一个很难的问题，司机听得很仔细，他一点都不懂但是他点着头好像他知道了。当那个人说完的时候，司机说：“我想这个问题很有趣，但是很容易，为了显示有多么容易，我将让我的司机来回答它."

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