Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient ...

Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient world slept only 6.5 hours a night.

现在我们周围的环境污染越来越严重。作为一个中学生，我们应节约资源，保护环境，从我们身边的小事做起，做一个“低碳生活”的中学生。请以“My Low--carbon Life”为题，写一篇短文描述自己的“低碳生活”。

大多数形容词（性质形容词）和副词有比较级和最高级的变化，即原级、比较级和最高级，用来表示事物的等级差别。原级即形容词的原形，比较级和最高级有规则变化和不规则变化两种。