这些短语的区别不很容易捉摸,一般来说：
get to know 了解,更靠近...以便了解
know 认识,知道,对...有知识
know of 用听过（但不曾有交往）,对...有表面上/肤浅的意识
know about 对...有一点知识（通过交往或别人告知）
例句：
Mary has known John for a year,but she wants to get to know him better.
I know this person.He works in my office.His name is John.
I know the book.I have read it.
I know of a place that sells this particular phone,but I have never shopped there.
I know something about this phone.It's made in China.It has an excellent camera.Its battery lasts a long time.And,it is inexpensive.
我是加拿大人,前英语老师