例句：

　　I sleep with the window open unless it's really cold.

　　天氣若不很冷，我總開著窗戶睡覺。

　　He works at night and sleeps during the day.

　　他晚上干活，白天睡覺。

　　How long can a human being go without sleep?

　　人不睡覺能活多久？

　　He took a long time getting to sleep that night.

　　他那天晚上過了好長時間才睡著。

　　You'll feel better for a good night's sleep.

　　你晚上睡個好覺就會覺得好些。