It's和This is的区别?Whose's this pen?It's my son's.This is his pen.这是课本中的原话,可到了做练习的时候题目答案是这样的：Whose's this dress.It's my son's.It's his dress.请问This is和It's有什么区别?这样用对么?加上dress不是指女装连衣裙么?怎么用到了son身上?

It's和This is的区别?
Whose's this pen?
It's my son's.
This is his pen.
这是课本中的原话,可到了做练习的时候题目答案是这样的：
Whose's this dress.
It's my son's.
It's his dress.
请问This is和It's有什么区别?这样用对么?加上dress不是指女装连衣裙么?怎么用到了son身上?