A small boy and his father were having a walk in the country when it suddenly began to rain very hard． They did not have their umbrella with them， and there was nowhere to hide from the rain， so they were soon very wet， and the small boy did not feel very happy． For a long time while they were walking home through the rain， the boy was thinking． Then at last he turned to his father and said to him，“Why does it rain， Father？ It isn't very nice， is it？” “No， it isn't very nice， but it's very useful，Tom，”answered his father．“It rains to make the fruit and the vegetables grow for us， and to make the grass grow for the cows and sheep．” Tom thought about this for a few seconds， and then he said，“Then，why does it rain on the road too， Father？”