Jim's father is ill, and his mother must look after him at home. So she says to her son, "Go to the hospital and ask a doctor to come here, Jim. ""OK, "says the boy, "but where is the hospital?" "In the town, " answers his mother.

Then Jim leaves his house. He gets to a crossing. He doesn't know the way. He stands there and thinks about where to go. Just then a farmer driving a carriage（马车）comes. Jim wants the farmer to take him to the town. "How far is the town from here?" asks Jim. "Two kilometers, "says the farmer. "May I take your carriage?" asks Jim. "Certainly. ""Thank you very much, "says Jim. He is happy and gets on the carriage. Half an hour later, the carriage doesn't get to the town. "How far is the town from here?" Jim asks again. "Four kilometers, "says the farmer. "Why is it farther now?" "The carriage is going in the opposite direction."