Question

a boy's who is 12 years old.

a boy's who is 12 years old.

Answer 1

句子有误，
应是：a boy who is 12 years old.
翻译成中文是：一个12岁的男孩。
相关短语学习：
years old
[词典] …岁（指年龄）;
[例句]Her son is three years old.
她儿子三岁了。

Answer 2

a boy's who is 12 years old.
意思是：一个男孩谁是12岁。
或者：一个12岁的男孩。

Answer 3

表达有误
a boy who is 12 years old.一个12岁的男孩

Answer 4

a boy's who is 12 years old
一个12岁的男孩