Richard lived with his mother when he was young. He didn't know who his father was. The woman did some washing for the rich and could buy only some bread for her son. So the boy was short and thin. One cold morning there was much snow in the streets. A truck hit the woman and the policemen took her to the hospital. Dying (临死) , she said to her son, 'Your father forsook (抛弃) me before you were born. It's his name and address.' Richard found his father, Mr. Cook, in. another city. It was one of the richest shopkeepers and he had to receive his son. From then on the boy lived a happy life. He ate all kinds of delicious food and wore beautiful clothes. But people often laughed at his rudeness (粗鲁). Once his father took him to a party. He saw a newspaper lying on the floor and picked it up while others were talking about a film. He had a look at it and found a car's wheels were upward (向上). He called out,' Oh, dear ! An accident happened !' All the people were surprised and began to read the newspaper. But soon they all began to laugh. Do you know why? Richard didn't know his father because ______.