【1】He has a mother who likes watching TV.【正确】【a mother这里a不表示数量。】
备注:以上侧重点说明“妈妈拥有某种爱好”相当于是His mother likes watching TV。或者 His mother’s hobby is watching TV.而不是说明有1个....的妈妈
【2】He has a mother, who likes watching TV.【正确】【a mother这里a表示数量。】
备注:以上侧重点说明“有一个妈妈”然后补充说明妈妈有某种爱好。相当于He has one mother and her hobby is watching TV. He has one mother and she likes watching TV.
以下2个句子和以上2个句子有所不同【按逻辑和常理,妈妈只能拥有1个,但儿子可以有1个或者1个以上。】
【1】The old man has a son who is a doctor.【限制性定语从句表示:不止1个儿子】
备注:以上侧重点说明:儿子不止1个,其中1个为医生。相当于The old man has three sons and one of them is a doctor.
【2】The old man has a son ,who is a doctor.【非限制性定语从句表示:仅仅只有1个儿子】
备注:以上侧重点说明:儿子仅仅只有1个,这个儿子是1名医生。相当于 The old man has only one son and he is a doctor.
以下2个句子和网友提供英语句子定语从句用法完全一样
【1】Tom has a mother who is beautiful.【定语从句起修饰/描绘的作用】
=Tom has a beautiful mother.
【2】Mary has a face which is beautiful .【定语从句起修饰/描绘的作用】
=Mary has a beautiful face.