I want to tell you the story of one of my old friends called Bob. His teachers called him A Troublemaker. They also said that he had no future and no hope. But now he owns a small second-hand bookstore store which makes him enough money to live on and also to support his mother. He told me that after he finished grade nine, he went to study at a technical college. He was a pretty bad student so he became one of the gang   leaders there. Many of them got caught many times for fighting. It looked like nothing could change his life. That was until one sad day when his father died. That changed everything. After his father died, his mother had to work very hard to make enough money to support the family. He told me that he really pitied his mum after his dad died. He felt that he needed to earn some money rather than let his mum work alone. He loved reading cartoon  books and had been collecting them for years. As his family was short of money, he decided that he should sell them. He did this by the side of the road where his mother was selling food. Soon he realized that his books were very popular. So he decided to set up his own business. He started his business by going around buying cartoon books from other people. He bought them for 25% and then sold them for half price. He could make enough money to help support the family. He was a troublemaker to his teachers but he is a hero to me. If you are judged as a bad student or as someone being stupid, I suggest you pay no attention to what they say. Just do your best in everything. Don't give up so easily. Believe in yourself. If you think that you can do it, then you can. Believe me, one day you could be more successful than those persons who looked down upon you. Bob decided to start his own business when he   _  .
sold all his cartoon books found others liked cartoon books could write his own cartoon books could buy cartoon books from others