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    “I will think of it.” It is easy to say this, but do you know what great things have come from thinking?

    Sir Isaac Newton was sitting in his garden when he saw an apple fall from a tree. He began to think and tried to find out why the apple fell. Then he discovered how the sun, moon, and stars are kept in their places.

    A boy named James Watt sat quietly by the fire, watching the lid of the kettle move up and down. He wanted to find out why the steam in the kettle moved the lid. From that time he went on thinking and thinking. And when he became a man, he improved the steam engine (蒸汽机) so much that it could easily do the work of many horses.

     James Ferguson was a poor boy. Once, seeing the inside of a watch, he wondered. “Why should I not make a watch?” But how could he get the materials to make the mainspring (钟表的主发条)? He soon found he could make it with whalebone (鲸骨). He then made a wooden clock which kept good time. His motto (座右铭) was “I will think of it.” And he made his thoughts useful to himself and the world. 

    Boys and girls, when you have a difficult lesson to learn, don't lose heart, and don't ask someone for help before helping yourselves. Think, and by thinking you will learn how to think to some purpose.

    In 1883, an engineer named John Roebling got an idea to build a bridge between New York and Long Island. However, bridge-building experts around the world thought that it was impossible. It had never been done before.

    After much discussion, he made his son Washington, a great engineer, believe that the bridge could be built.

    The project started well, but a few months later, an accident took the life of John Roebling. Washington was badly hurt and he was not able to walk or talk. However, Washington never lost his heart. He still wanted to complete the bridge. But all he could do was to move one finger. So he decided to make the best use of it. By moving his finger, he slowly developed a way of communicating with his wife.

    He touched his wife's arm with his finger, “telling” her that he wanted her to call the engineers again. Then he used the same way to tell the engineers what to do. The project carried on again.

    For 13 years, Washington tapped out (敲出) his instructions with his finger on his wife's arm, until the bridge was finally completed. Today the Brooklyn Bridge stands as a monument(纪念碑) to one man's unbeatable spirit.

    It is also a monument to engineers and their teamwork, and to their faith in a man who was considered crazy by half the world.

    On the first day in her new house，Mouse wrote a letter to her old friend.

    On the way to the post office, Mouse saw Beaver. He gave Mouse a big smile.

   "Perhaps I should say hello, "thought Mouse." Beaver's teeth are so long and sharp（锋利的）. Beaver wouldn't make a good friend. Not like Vole, whose smile was kind." So Mouse left without saying hello.

    After lunch, Mouse heard a knock on her door. Then she peeked（偷看）out the window. It was Squirrel.

   "Perhaps I should invite her in for tea, "thought Mouse." But Squirrel talks a lot. Squirrel wouldn't make a good friend. Not like Vole, who always listened." So Mouse didn't open the door.

    That night, Mouse looked at a picture of herself and Vole. She thought back to the first time she met Vole. She remembered feeling afraid-afraid of Vole's eyes and Vole's large size.

    In fact, Vole had seemed so different that Mouse almost decided Vole wouldn't make a good friend.

    Mouse realized something." I made a mistake!" she cried.

    The next morning, Mouse made some cakes and put them in a basket.

    She went to Beaver's house first, and next to Squirrel's house.

    When Mouse returned home, she was smiling. She went to her desk and wrote a letter to Vole.