其实safer就是一个形容词的比较级，形容词如何使用，safer 就可以怎样用，下面举例说明：
It is much safer to live in the houses than in the tall buildings. 住在平房子里比住在高楼大厦里要安全很多！再比如 Living in China is safer than living in the United States of America because American people own guns.
总结起来就是safer 通常是在有比较的情况下使用！
