1.be the same age as sb. 和某人一样的年龄。
be the same as 与……一样 at the age 在……的年龄
只是be the same as 后面加某人
2.as old as sb. 和某人一样的年纪
as……as 同样有“与……一样”的意思
只是:as +形容词+as+某人
be of the same age with sb
they are of the same age
be of an age with sb
someone is as old as someone
be at the same age of someone