A problem with my sister's room

Recently, my sister has had to live in a dark room because the lamp has been broken down for 2 weeks. I’m too lazy to help fix it for her. My father told me to repair it many times, but I am still lazy. I intended to go to a convenience store to buy a new lamp. Unfortunately, I had no money. For more than 1 weeks my sister has been going to go to school to study and she needs the light to study in her room, so I think I have to go to buy a new one soon for her. I’m very sorry about that. She can’t use her room to do anything at night. Every night, when she finishes her meal, she usually goes to the living room to watch television with my parents and then when the film is finished, she usually goes to her private room to sleep. I have promised with her, I’m going to buy a new lamp soon. I’ll give her a surprise in this week. I hope that she will be happy.