限制从句和非限制性从句区别

限制性定语从句和主句之间关系密切,去掉后会影响主句内容,且不用逗号和主句分开.但非限制性定语从句和主句内容不十分密切去掉后不会影响主句内容,且用逗号与主句分开,在引导词上只有that不能引导非限制性定语从句,任何关系词不能省略.
His son who works as a teacher came to see him yesterday.他当老师的儿子昨天来看他.(说明他的儿子不只一个)

His son ,who works as a teacher came to see him.他儿子昨天来看他,他儿子是老师.(他只有这一个儿子)_