(1) back of在美式口语中用作介词短语，等于in back of，表示：
①在……后面，等于behind, in the rear of。
- Our car was (in) back of theirs at the traffic light.
在红绿灯前，我们的车在他们的车后面。 - There's a store-room back of this house.
在这所房子后面有一间贮藏室。
②在……(时间)以前。
- There used to be some rough low shacks here ten years back of this.
10年前这儿有一些粗陋、低矮的棚屋。
(2) at the back of与in (the) front of相对，常用于口语中，表示：
①在……后面/部，可指房屋、汽车等里面的后部，也可指整个房屋或汽车外的后面。用于前者时，可与in the back of换用。
- There is a post office at/in the back of the house.
房子后面有个邮局。 - I like to sit at/in the back of the room whenever we have a meeting.
我们一开会我就喜欢坐在房间后部。 - Three people can sit at/in the back of the car. (...on the back seats of the car)
车后部可坐三人。
②支持。
- The workers on strike have at their back the deep sympathy and firm support of the general public.
罢工工人背后有广大群众的深切同情和坚定支持。
③作为某事背后的原因。
- At the back of all this lies the conviction that the leader's foresight of development may be relied on.
在这一切的背后，凝聚着人们对这位领导人所具有的发展眼光的可靠性的坚定信心。 - What's at the back of it?
这件事背后有什么文章?
(3) in back of常用于美式口语中，意为“在……后面”，等于in/at the back of, back of。
- There is an index (in) back of the book.
＊这时，也可用in the back of, at the back of。
- There is a glossary in/at the back of the reader.
这本读物后面有一个词汇表。
(4) ①on the back of意为“在……的反/背面；在……的背上”。
- There is a very good song on the back of the record.
在唱片的背面有一首非常好听的歌曲。 - I rode up on the back of the donkey.
我骑在驴背上。
②on the back of还有“在……之后不久”的意思。
- The child had a bad cold, and then on the back of that came measles.
这个孩子患了重感冒，其后不久又患了麻疹。
