It is true that many students at school these days are suffering from a serious lack of sleep. Many of
them feel tired and lose their interest in studying. 　
     Take my classmates and me as examples. Now we're students in Grade Eight. We have a lot of books
to read and we have to study hard every day. When we get home after evening classes, we still have a lot
of homework to do. When we finish our work, it is often eleven or twelve o'clock. Therefore, some of us
fall asleep in class during the day. 　
     To solve this problem, we need time for more exercise to make us physically healthy. Also, teachers
should give less homework to us. Most important of all, measures should be taken to improve the education
system.

根据短文内容，用适当的单词填空，使句子的意思完整、正确。每空限填一词。
1. Some students feel tired because they don't get enough _________.
2. This is my ________ year to study in the middle school.
3. We don't finish our homework _________ it is often eleven or twelve o'clock.
4. Doing ________ is a good way to keep ourselves healthy.
5. Students hope to get _________ homework from their teachers.

A. to              
B. up          
C. out            
D. with