drop in on . call on or visit somebody unexpectedly顺便拜访

If you are ever in our neighbourhood，be sure to drop in on us．如果你到我们这个地区来，一定要来我们这儿玩玩。

Why don't we drop in on her and find out how she is doing？我们何不进去坐坐，顺便看看她干得怎么样？

drop off . fall off掉下

My top button has dropped off and I can't find it ．我最上面的钮扣掉了，找不到了。

drop off . become fewer or less；decline 减少；下降

The number of students has been dropping off recently．近来学生人数减少。

Sales have been dropping off badly．销售额下降得厉害。

Attendance at football matches has dropped off since the coming of television．自有电视以来，到现场观看足球比赛的人就减少了。

drop off . fall asleep睡着

I was just dropping off when the telephone rang．我刚要睡着，突然电话铃响了。

drop off . let somebody get down from a vehicle；set down让某人下车；放下

Where do you want me to drop you off？你要我在哪儿让你下车？

Tom dropped me off at the post office and I've walked the rest of the way．汤姆让我在邮局下了车，剩下的路我就步行了。

He said he would drop the parcel off at the post office．他说他要在邮局寄一个包裹。

I can drop the laundry off on my way to work．我可以在上班的路上把要洗的东西送掉。

drop out . leave；cease to attend离去；不出席

A few had even dropped out，but nearly half of these had returned to graduate．少数人甚至已辍学，但近一半的人又返校以求毕业。

She has dropped out of society．她已经退出社交界。

When Peter saw that he hadn't a chance，he dropped out of the race．彼得看出他没有获胜的机会时，就退出了比赛。

drop to one's knees . kneel down跪下

The man dropped to his knees，begging for mercy．那人跪了下来，请求宽恕。

dry off . （cause to）become dry变干；弄干

Dry yourself off thoroughly after swimming，or you might catch cold．游泳之后要把身体擦干，否则可能感冒。

dry out . become very dry变干

We can't use this wood，because it is not dried out．我们不能用这木头，因为它还没有干透。

I don't know when the ground will dry out．我不知道地面何时才能干？

dry up . become completely dry干涸

The lake has dried up．那湖干涸了。

dry up . lose inspiration；fail to produce words；stop talking（灵感）枯竭；忘词；说不出话来；停止说话

His power of invention will never dry up．他的创造力永远也不会枯竭。

The play was good， but one of the actors was nervous and dried up twice in the second act．戏演得不错，但是有个演员太紧张了，在第2幕里有两次忘了台词。

The speaker suddenly dried up in the middle of his speech．演讲者在讲话中间突然说不出话来。

Dry up！Don't say any more！住嘴，别再说了！

I won't dry up；I must say something about it ．我不会不说话的，我一定得对这件事发表意见。

due to . caused by；because of；owing to；thanks to由于；因为；由…造成

The accident was due to careless driving．这场车祸是粗心驾驶造成的。

What would you say inflation is mainly due to？你认为通货膨胀的主要原因是什么？

He arrived late due to the storm．他由于暴风雨而来迟了。

due to .attributable to归于

His success was largely due to his hard work．他的成功在很大程度上归功于他的辛勤劳动。

The credit is due to you．荣誉应该归于你。

Respect is due to older people．年长者应受到尊敬。

The first place is due to the chairman．首席应给主席。

What is the amount due to you？欠你多少钱？

due to .expected or scheduled to arrive or be ready；supposed to do 预期的；应到的；预定的

The train is due to pull in at half past five a.m.火车预定早上5点半到达。

Professor Smith is due to give us a lecture at eight tomorrow morning．史密斯教授预定明天上午8点给我们演讲。

dwell upon . dwell on . think， often too much about something esp．troublesome;worry over something 老是想着（某事）

Don't dwell on thoughts that annoy you．别老想着使你烦恼的事。

dwell upon . dwell on . speak or write at length about something 详述

The teacher was always dwelling on the boy's faults．老师总在数落这个男孩的过失。

Don't dwell too much on the subject．这个题目不要讲得太详细。

The speaker dwelled on traffic safety in his talk．演讲者详述了 交通安全问题。

earn a living . make a living . get what is necessary for life 谋生

Industrious as he is， he can barely earn a living．他尽管勤勉也只能勉强维持生活。

ease in . be accustomed gradually 逐渐适应

Don ' t worry！You'll be eased in to the new job．不要担心！你会渐渐适应新工作的。

He is gradually eased in to the weather here．他慢慢地适应了这里的气候。

ease in . move or place something carefully into a position 小心地把某物移入或放入某一位置

He eased the bolt in carefully．他小心地插上插销。