I went to my sister who lives in New York .
In this sentence , I have more than one sister and I went to the one who lives in New York and not to the one who lives in Homs..
I went to my sister , who lives in New York .
In this sentence, I have have only one sister.
In the first sentence,
who lives in New York is a defining relative clause
or a restrictive clause
As you know defining relative clauses are not separated from the antecedent by a comma. They give necessary information . They are unlike non-defining clauses , which are separated from the antecedent by a comma, and give extra information.
It is wrong to say or write
I went to my father who lives in london.
This means that you have a father who lives in London and another one who lives in Egypt. . ( oh My God ! )
You have to say and write :
I went to my father , who lives in London.
who lives in london. معلومة إضافية عن والدك وهي وليست محددةأو معرفة لأبيك
اقتباس:
A relative clause is a subordinate clause that begins with a question word (e.g. who, which, where) or the word that.
A relative clause is a subordinate clause that is inrtoduced by a relative pronoun such as
which ,
who ...etc.
Do not mix between a wh - word a nd a relative pronoun.