Mr. Fern was born in a big city. His father owned several companies and earned a lot of money. He could give his son all the young man wanted. He was busy with his business and never asked him how he got along with his studies. So the boy spent most time in the restaurants or cinemas. Of course he was not good at his lessons and learned nothing at school. He made many friends but none of them was good and when they knew he came from a rich family, they began to teach him to gamble(赌博). Of course he lost much money. Now Mr. Fern was twenty and finished middle school. He could do nothing. But his father didn' t mind it until one day he found the young man had sold one of his companies. He became so angry that he made him leave his house. The young man couldn' t gamble any longer. His friends made him pay his debt. He had to ask his mother to help him and the woman often gave him some money. But one evening his father happened to find it. The old man stopped his wife from doing so. They began to fight in the room. The young man brought out a knife and killed Iris father. His mother helped him run away, but soon after that he was caught and sentenced(判刑)to death. It was a cold and wet day. Suddenly it began to rain heavily when Mr. Fern was being sent to the execution ground(刑场). Soon he and the soldiers were wet through. He said angrily, 'Bad luck! I shall be shot in such bad weather !' 'Don't complain(抱怨), brother,' said one of the soldiers. 'You' re luckier than us all. We'll have to go back to the city after that!' Old Fern never wanted to know about his son' s studies because ______.