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。