题目内容：

根据句意及汉语提示填空。

1.Getting up early is a good _______ (习惯).

2. Driving carelessly _______ (引起) accidents.

3.He isn’t at school now. _______ (或许) he is at home.

4. Xu Xiao taught himself on the _______ (互联网).

5. We sleep _______ _______ (至少) 8 hours every day.