drop across

1. 偶然碰上

I dropped across Mr. Smith yesterday.

我昨天偶然碰上史密斯先生。

drop away

1. 一滴滴漏掉

The oil was dropping away.

油正在一滴滴漏掉。

2. 离开

The guests dropped away one by one.

客人们一个一个地离去。

drop back

1. 落回

The small ball dropped back to the floor.

小球又落回到地板上。

2. 落后

The car dropped back halfway through the race.

那辆车跑了一半赛程就落后了。

drop behind

1. 落伍; 落后

The production of the factory has been dropping behind in the last few months.

那家工厂的生产量近几个月来一直在下降。

drop by/in

1. 顺便拜访

Would you drop by when you are in town?

你来城里就来玩好吗?

drop into

1. 顺便走进

He dropped into a roadside store.

他顺便走进一家路边的商店。

2. 不知不觉进入(某种状态)

She soon dropped into a sound sleep.

她很快就睡熟了。

drop off

1. 让……下车

Please drop me off at the bank.

请让我在银行下车。

2. 减少; 下降

The business of the company was dropping off.

这家公司的生意日益清淡。

3. 睡着

She dropped off during the sermon.

她在听布道时睡着了。

drop out

1. 脱离

Luckily, I dropped out before the deal turned sour.

很幸运的, 在交易变坏前我已退出了。

One of my teeth has dropped out.

我的一颗牙齿掉了。

2. 退出; 退学

She dropped out of school to become a waitress.

她退学去当女招待。