阅读下面短文，并借助上下文补充所缺信息。每个空格只能填写一个形式正确、与短文内容意思相符的英语单词。

    We know many students don't have enough (足够的) sleep. Many students say they go to bed early. They stay up late because they have to lots of homework and they like watching TV and playing computer games at night. A survey (调查) shows that 1/4 students don't get eight sleep every night. They often feel and want to sleep in class. In Scotland, some schools start new subject, Sleep Class. The teachers teach the students to sleep well. Many students like this subject. They think it's good for their health their study. A 15-year-old boy says, "Now I go to bed 10:00 every night. The next day, I usually get up time and then play sports for an hour. I very great. "