根据短文理解，从四个选项中选取最佳答案填空。
Middle school can be hard for school children. They would like 1good grades. They also want to have their own hobbies, keep cool and make friends. 2 it's difficult for them to do all the things well at the same time because they have a lot to do both in school and after school.
Jane is in Grade 9. She is good at her lessons and gets good grades in exams. But she 3 school clothes but likes fashionable girl clothes very much. She also likes to 4 pop music every day. However, she is too busy with her lessons at school. And she has too much homework to do at weekends. So she has5 time to keep her hobbies. And heavy schoolwork 6 her feel tired and unhappy. She is now worried about herself a lot.
Bill is now in his Grade 11. He loves his school life. He did best in his class in Grade 10. But this year he 7 interested in 8 football. He plays football every day and he plays it 9. Although he tries his best, he didn't do better than last year in his lessons.
10can go well if you use your head. But never only think about keeping cool.
（a＞b＞0），则有（ ）