On a street corner in a busy town there lived a boy named Billy.His father was a policeman，whose work was to help old people and children cross the streets safely.Billy was proud of his father and wanted to be like him. "Some day，" he said to himself，I will be a policeman，too.Then I will help people to cross the streets.
    Near Billy's bedroom window was a big tree.He often saw a mother squirrel sitting close to her nest.Sometimes Billy put peanuts outside his window，and it wasn't long for the sharp eyes of Mother Squirrel to see them there.Down she would come on a long branch of the tree.Quickly she would pick up a peanut，put it into her mouth，and run away quickly.
    Mother Squirrel had a family of four tiny gray squirrels.How excited Billy was the first time he saw them sitting outside their nest!They learned to jump from one branch to another，run up and down the tree trunk and follow their mother where she went.
    One Saturday morning Billy was gathering the grass with a rake—a garden tool with a long handle.Suddenly an excited sound told him that something was happening.Instantly Mother Squirrel came down the tree.One by one，the little squirrels followed her.The smallest squirrel was the very last.Across the street from Billy's house was a garden in which grew a walnut tree.It was to this tree that Mother Squirrel wanted to take her family.She ran to the sidewalk，and in a moment was safely across the street and ir the garden.The little squirrels followed except the last little one，because he could not run so fast.
    Just as he reached the street，along came a big automobile.He was so frightened that he looked for some safe place to hide in.A dark hole like his nest was the best place he knew.So he jumped into the first hole he saw.It was the opening to a sewer（下水道）at the corner of the street.The poor baby squirrel tried to climb up the wet sides of the hole，but could not get out by himself，and he was too far away to call his mother.Billy knew how to help.

注意：
（1）寫作詞數(shù)應(yīng)為150左右；
（2）請(qǐng)按如下格式在答題卡的相應(yīng)位置作答。
    The thought that he was a policeman's son reminded him of the rake in his hand.
                  
    Mother squirrel heard the lost one sing when Billy put him down on the grass.