对话填空（共10小题：每小题1分，满分10分）请认真阅读下面对话，并根据各题所给首字幕的提示，在答题卡上标有题号的横线上，写出一个英语单词的完整、正确形式，使对话通顺。
M: How come David is always so full of (76) e______?
W: He has a strange but highly (77) e______ way of sleeping.
M: What is that?
W: He takes a short sleep for an hour every six hours and has a (78) t______ of four hours of sleep every day.
M: Where did he get that strange (79) i_______?
W: He read from a book which (80) s_______ it was the best (81) w______ for human beings, and he believed it.
M: How many hours do you sleep a day?
W: I need at least 7 hours. I once tried to follow David’s (82) e_______, but it never (83) w______ out for me.
M: If I sleep (84) d_______ the day, I can never wake up.
W: Not everyone is David, I (85) g______.