Xiao Long is the only one（）was born in 1990 in our classthat 还是who?

Question

Xiao Long is the only one（）was born in 1990 in our class
that 还是who?

Answer 1

Xiao Long is the only one （that） was born in 1990 in our class.
小龙是我们班上唯一一个1990年出生的人.
括号中要填的是定语从句的引导词.因为先行词有the only（唯一的）作修饰语,所以不能用who,而只能用that来指代先行词,并在从句中作主语.