die off . （a group of living things）die one by one 相继死去

The chickens are all dying off from the disease．小鸡一个个地病死了。

The leaves of this plant are dying off．这植物的叶子正在凋落。

die off . become extinct 绝种

It would be a pity if these birds are allowed just to die off．如果让这些鸟绝种，那就太可惜了。

die out . cease to exist；disappear gradually and completely 灭绝；消亡；渐渐完全消失

Many old customs are gradually dying out．许多旧习俗正在日渐消失。

If too many of these rare animals are killed，their kind will die out．这种稀有动物如遭大规模的捕杀就可能灭绝。

differ from . be different from 与…不同

The orange differs from the potato in nearly every way．桔子和土豆几乎在各方面都不相同。

differ from . disagree with 与…意见不同

I differ from him on the matter．I differ from him about the matter．我在这个问题上同他意见不一致。

different from . different than . unlike；not of the same kind as 和…有区别；与…不同

This novel is different from that one in both style and content．无论在文体或内容方面，这部小说和那部小说都不同。

She is very different from her sister．她与她妹妹大不一样。

He is different from what he was ten years ago．他已不再是10年前的他了。

How different life today is than what it was fifty years ago！今天的生活与50年前的生活多么不一样啊！

dig in . work hard；begin to work 勤勉工作；努力干；开始干起来

My son dug in and finished his homework very quickly．我儿子很认真，很快就把家庭作业做完了。

If you expect to finish all this work in two hours，you'd better dig in．如果你想在两小时之内完成这项工作，就得马上干起来。

dig in . begin eating with appetite津津有味地开始吃起来

The boys dug in ravenously．男孩们开始狼吞虎咽地吃起来。

Dinner's ready．Dig in， everybody！晚餐已准备好了，大家吃吧！

dig in . protect oneself by digging a trench，； cover by digging挖壕沟等以藏身；把…埋在土里

The company commander ordered his soldiers to dig themselves in．连长命令战士们挖战壕，以便掩蔽。

The soldiers have dug in along the river．士兵们沿河边挖了战壕。

Dig this chemical in and crops will grow faster．把这化肥埋进土壤里，庄稼就会长得更快。

dig in . establish oneself firmly in a position，巩固自己的地位等

He has been working in this department for ten years and he's pretty well dug himself in．他在这个系工作已经10年了，已经站稳了脚跟。

dig in . stick to one's own idea坚持自己的意见

When facts have shown that you are mistaken，you mustn't dig in．当事实已经证明你错了，你就不应该再坚持自己的意见。

dig into . eat heartily； eat with appetite 痛快地吃；大吃

They were so hungry that as soon as supper was served，they dug into it hungrily．他们饿极了，晚饭一端上桌，他们就狼吞虎咽地大吃起来。

dig into . delve into；investigate thoroughly努力钻研；彻底调查研究

When he digs into a problem he does not give up until he gets to the bottom．他要是钻研一个问题，就非弄个水落石出不可。

The detectives are digging into this whole business．侦探们正在彻底地调查整个事件。

He is digging into Chinese history．他正研究中国历史。

dig into . apply oneself to集中精力做；全力以赴地干

They dug into their work with a will．他们全力以赴地工作。

dig into . make inroads on（savings，）侵占；动用（积蓄等）

They were forced to dig into savings to pay their current debts．他们被迫动用存款偿付债务。

dig out . remove by digging；discover by digging挖走；发掘出

The gardener dug out the weeds．园林工人铲除了杂草。

They are digging out a large ancient tomb．他们正在发掘一座古墓。

dig out . 挖；掘成

They are digging out a tunnel．他们正在挖一条地道。

dig out . release； rescue by digging通过挖掘救出

He was buried under the avalanche and had to be dug out．他被埋在雪堆中，必须把他救出来。

The rescuers managed to dig out the trapped miners．救护人员设法挖出了困在矿下的工人。

Some people are still being dug out of the ruins of the building．人们仍在挖掘压在建筑物废墟里的一些人。

dig out . find out；obtain发现；取得

Through investigation they have dug out all the facts．通过调查，他们已弄清了所有事实。

Where on earth did you dig out these old clothes？你究意是从哪儿翻到这些旧衣服的？

dig up . bring to light by digging what has been buried or hidden因挖掘而发现

An old Greek statue was dug up here last month．上个月这里挖出了一座古希腊雕像。

The archaeologists have dug up a remarkable collection of historical relics．考古工作者发掘出一大批历史文物。

These relics were dug up last year．这些文物是去年出土的。

dig up . make a money contribution出钱

We all dug up to keep the poor on relief last month．上个月我们大家都出钱救济穷人。

dig up . find or get something  with some effort发现；找到

The girl dug up some useful material for her English composition．这女孩为写她的英文作文找到了一些有用的资料。

The newspaper loves to dig up scandals．报纸喜欢揭露丑闻。

He always manages to dig up a fresh excuse for being late．他总能为他的迟到找到这样那样的新借口。

dig up . break up,（land）by digging；remove from the ground by digging 翻土；自地上挖掉

They are digging up land for a new garden．他们正在翻土建一个新花园。

They want to dig these trees up to make the street wider．他们想把这些树挖掉拓宽街道。