如图是一种游泳辅助装备．它由一个气囊和腰带组成，两者之间由一根线连接．正常游泳时，连接线是松弛的，气囊漂浮着，跟人如影相随．在体力不支等情况下，可将气囊压入水中，防止人下沉，在此情况下（　　）

      Mrs. Herry lived in a city of America. Her husband had a few big stores. Two years ago the rich shopkeeper was hit(被撞) in a traffic accident. He was taken to a hospital at once, but the doctors could not save him and he soon died. He left his wife plenty of money, but the woman was very sad. She sent(打发) all servants(佣人), cooks and drivers away and began to live alone. But she took good care of Bobby, her husband's dog. And she can't leave him now.
      One summer afternoon, Mrs. Herry went to do some shopping. Suddenly it began to rain, so she had to take a bus. As soon as she got on, she said to the driver, “Can you look for a seat for my dog if I buy a ticket for him, Sir? ”
    The driver had a look at the dog and found its legs were very dirty. He said, “Of course I can, Madam. But he must sit on the seat like you do!”
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