介词off 的意思为: 从……落下，离开，从……去掉，下班。总之，是“离开”的基本含义。

1.作状语

He took his feet off the desk when the manager entered the office.

当经理走进办公室的时候，他把脚从桌子上拿下来。

I took the key to the room off a shelf above her head.

我从她上方的架子上拿走了房间钥匙。

Don't try to get on or off a moving train.

火车运行时，请勿上下车。

The local police had warned visitors to keep off the beach at night.

当地警方告诫游客不要在夜间去海滩。

(当地警方告诫游客夜间要远离海滩。)

2.作定语

Lily lives in a penthouse just off Park Avenue.

莉莉住在公园大道附近的一套顶层豪华公寓里。

3.作表语

Most pregnant women remain off cigarette while carrying the child.

大多数孕妇都在孕期戒了香烟。

常用的短语有:

get off... 下车

fall off... 从……上掉下

keep off... 远离……

be off... 远离……