题目内容：

根据句意和首字母提示完成下列句子。

1.There are sixty m___________ in an hour．

2.He is ill, and his i__________ makes us feel sad．

3.A lot of t__________ are visiting the Great Wall, so it is very crowded．

4.Good food and e__________ help me to study better．

5.It is n_________to eat a balanced diet.