Is this man ( ) l met yesterday .说明为什么

问题描述:

Is this man ( ) l met yesterday .
说明为什么

that

填who吧,who用来引导一个定语从句,修饰the man ,后面的I met yesterday 是定语从句的内容

who,或者that.
定语从句l met yesterday修饰先行词man,that可指代人或者物,who只能指代人.