请问：by, near, next to, beside这几个介词的意思有何区别?

by,beside,near和next to
1) by和beside均表示“在……旁边”,常可换用
例：There is a chair by the table.桌子边上有一把椅子.
She stood by the window.她站在窗边.
The hotel is beside (/by) the river.那家饭店在河边.
Come and sit beside (/by) me.过来,坐在我边上.
Put your shoes beside mine.把你的鞋子放在我的鞋子旁边.
2) near表示“在……附近”,表示的距离比by和beside稍远些,也时常换用
例：There is a theatre near his home.他家附近有一家剧院.
Don't play near the road.不要在马路附近玩.
There is a post office near No.1 Middle School.第一中学附近有一所邮局.
3) next to表示“紧靠……的旁边”
例：The new building next to the bookstore is a cinema.书店旁边的那幢新楼是一家电影院.
There is a café next to the barber's.理发店隔壁是一家咖啡馆.