1、吉姆明天要考试了，可他一点也不担心 2、昨晚我完成作业才睡觉 3、这本书它太难了，我看不明白

中译英？
1. Jim is going to have an exam tomorrow,but he isn't worried (about it) at all.
2.I didn't go to bed until I finished my homework last night.
3.The book is so difficult for me to read that I can't understand it.