题目

  How can we all get more laughter into our lives? Here is what the experts suggest: __71__.Nancy Alguire, a teacher in Clifton Park, N. Y., was once painfully shy and had a hard time laughing. Then she married a circus clown (小丑) . I became interested in the clowns, she recalls One day I put on a costume and painted my face. That afternoon my whole life changed. I learned to laugh and enjoy life in a way I had never done before. __72__ To this day, she still makes it a rule to be with people who enjoy life and laughing. __73__ It doesn't take you too much time and can be easy. 20．下列实例中，目的是为了增大压强的是（　　）A．书包带做得较宽B．刀刃做得很薄C．坦克装有宽大的履带D．大型平板拖车装有很多轮子