mug up . learn thoroughly，usually for an exam（考前）拼命强记；攻读

It is no use mugging up those formulas without mastering them．不掌握公式，光是强记是没有用的。

I've forgotten nearly everything that I mugged up for the．last exams．以前考试时强记的东西我现在已忘得差不多了。

He's mugging up history for the exam．他正在死记历史以应付考试。

mull over . consider or think about something 对…琢磨；思考

He's asked for a bit more time to mull over my proposal．他要求给他点时间来考虑我的提议。

He wanted the the chance of mulling over his conclusions about the subject．他希望有机会仔细考虑一下他对这个问题的结论。

He mulled the idea over in his mind．他脑子里反复思考这个主意。

muscle in . force one's way in强行进入；强夺

He tried to muscle in on the meeting，but they threw him out．他想强行进入会场，但他们把他赶了出来。

We don't want any of the big companies muscling in on the project．我们不希望任何一家大公司强取这一工程。

The gang has muscled in on their rivals' territory．这伙匪徒强行进入了他们对手的地盘。

 muster up . develop；gather鼓起；奋起

He mustered up courage to climb the cliff．他鼓起勇气攀登那个峭壁。

Muster up your courage．The difficulty will soon be overcome．鼓起勇气来，困难很快就会克服的。

He mustered up all his courage for the ordeal．他鼓足勇气去经受严峻的考验。

N

nail down . make secure by using nails用钉子钉住

If the corner of the carpet curls up，nail it down．要是地毯的角卷起了，就把它钉牢。

nail down . settle definitely；make sure确定；肯定

Joe had a hard time selling his car，but he finally nailed the sale down when he got his friend Sam to give him three hundred dollars．乔的车很难脱手，在他朋友山姆出价三百美元时，他终于做成了交易。

Our company has just managed to nail down a new，contract worth sixty thousand pounds．我们公司刚设法确定了一份价值六万英镑的新合同。

nail down . make somebody express his position，opinion，要（某人）把话讲明

It is impossible to tell how much truth there is in his allegations as he refuses to be nailed down．要说出在他的断言中有多少真实性是不可能的，因为他不肯讲明白。

The more we try to nail her down，the more she refuses even to talk about the issue．我们越是想让她讲明白，她越是拒绝谈论这个问题。

nail down . insist on somebody keeping a promise，an undertaking，坚持要（某人）遵守诺言等

I'm not going to be nailed down to a particular date for completing the work．我不打算受在某个特定日期完成任务的约束。

nail down . make agree使同意；使应允

See if you can nail him down to accepting our offer．看你能否使他同意接受我们的帮助。

I nailed him down to coming at six．我让他一定在六点钟来。

name after . give the same name as用…命名

The substance was named after its discoverer．这一物质是以其发现者的名字命名的。

The boy was named after his mother．这个孩子是以他母亲的名字起名的。

narrow down . become narrow；become limited；reduce变窄；缩小；减少

The path has narrowed down a lot since I was last here．自我上次到这里以来，这条路已窄了许多。

The selection committee has narrowed down the original pile of applications to just these five．选拔委员会已把原来的一大堆申请书缩小到这五份了。

The whole question narrows down to who is going to pay for all the damage．整个问题只剩下该由谁来赔偿损失了。

They have narrowed the search down to this area of the town．他们已把搜查范围缩小到该市的这个地区。

near at hand  . close by在近旁

You should always have a good dictionary near at hand．你手头应当一直有一本好词典。

Fortunately there was a hospital near at hand and they took the man there．幸好附近有所医院，他们就把这人送到那里去了。

near at hand  . soon to happen即将发生

The examinations are near at hand．考试即将来临。

The day when he will have to be punished is near at hand．他很快就将受到惩罚。

 neck and neck . close together；side by side；with no advantage over the other in a race并驾齐驱；不分上下

The two long-distance runners were neck and neck all the way to the finish line．两个长跑运动员一直到终点都是并驾齐驱，不分上下。

The two race boats seemed neck and neck as they rounded the final curve．两条赛船在驶到最后一个拐弯处时似乎并肩而行，不分胜负。

 neglectful of . in the habit of neglecting things常常忘记

She works so hard that she is often neglectful of her family．她工作非常卖命，常常连家都忘了。

He is often neglectful of his promise．他常常言而无信。

neither fish， nor fowl . neither flesh， nor fowl . something or somebody that does not belong to a definite group or known class非驴非马；不伦不类

Mrs．Harris bought a piece of furniture that was both a table and a chair．Mr．Harris said it was neither fish nor fowl．哈里斯太太买了一张桌子兼椅子的家俱，她先生说那是不伦不类。

That book is neither fish，flesh，nor fowl．这本书写得不伦不类。

neither here nor there . not important to the thing being discussed不重要；与题目不相干

He talked for two hours but his remarks were neither here nor there．他讲了两个小时，但尽说些不相干的话。

What you have just said is neither here nor there．Try to keep to the topic．你刚才所讲的与题无关，要尽量扣紧主题。

neither…nor…既不…也不…

Neither you nor I nor anybody else knows the answer．你我以及其他任何人都不知道这个答案。

It is neither blue nor green．它既不是蓝的，也不是绿的。