题目 184

类型：RegExp 正则对象

题目：请利用正则将字符串 these size coresponds to 8px, 12px, 16px. The default size is small, A.K.A. 8px 中的大写字母转为小写。

期望：these size coresponds to 8px, 12px, 16px. the default size is small, a.k.a. 8px