turn to . apply oneself to致力于；专心于

Yes should turn your thoughts to study．你应该致力于学习。

turn up . appear出现

He said he would come， but hasn't turned up yet．他说他会来的，但是还没有到。

turn up . increase增加

Please turn the radio up;I'd like to listen to the news．请把收音机音量开大一些，我想听听新闻。

 turn upside down . throw into confusion混乱一团

The house was turned upside down by the burglars．屋子里被盗贼弄得乱七八糟。

U

under a cloud . under suspicion； not trusted被怀疑

With the theft of the jewels cleared up， he was no longer under a cloud．由于珠宝盗窃案已经查清，他不再受到怀疑了。

 under age . too young； not old enough； below legal age未成年的；未到法定的年龄

He could not join the army because he was under age．他不能参军，因为他不够年龄。

The son cannot have the control of his property，for he is under age．儿子因为尚未成年，所以不能占有他的财产。

under color of . on the pretext of以…为借口；在…的幌子下

There are infamous hypocrites who promote their own advantage under color of the public good．有些无耻的伪君子假公济私，谋取私利。

The man extorted money under color of philanthropy from quite a number of people．那人打着慈善的幌子，从不少人那儿捞取钱财。

 under consideration . being considered；given careful thought在考虑中；在研究中

Your proposals are still under consideration．你的建议仍在考虑之中。

The matter is at present under consideration．那件事目前正在考虑。

under control . under authority；under restraint 在…控制之下

They have got flood waters under control．他们已使泛滥的洪水受到了控制。

I noticed that my legs are not well under control．我发觉我的两条腿不听使唤。

under correction . knowing that one may need to be corrected不一定全对；有待指正

That is my opinion，but I speak under correction．那只是我的看法，请指正。

under cover . hidden；concealed隐藏；掩蔽

He kept his invention under cover until it was patented．在取得专利权以前，他对他的发明一直保守秘密。

 under lock and key . securely kept妥善保管；置于极安全之处

The important documents are all under lock and key．重要文件都已妥善保存起来了。

under no circumstances . never；whatever may happen决不；无论在何种情况下都不

I made up my mind that under no circumstances would I agree to such a decision．我决心在任何情况下都不同意这样的决定。

 under somebody 's nose . under the nose of . in an easily seen or noticeable place 在…眼前；在明显的地方

The thief walked out of the museum with the painting，right under the nose of the guards．那位小偷带着名画，就在守卫人员的众目睽睽之下走出了博物馆。

 under the sun . on earth；in the world（used for emphasis）在世界上（用于强调）

Nothing under the sun is too difficult if you set your mind to it ．世上无难事，只怕有心人。

The President's assassination shocked everyone under the sun．总统的遇刺使全世界为之震惊。

under the weather . unwell，although not seriously ill 不舒服

Brian is feeling under the weather，so he's going to bed early tonight．布莱恩不舒服，因此今晚他睡觉很早。

I was a bit under the weather last week，but I'm all right now．我上星期身体有点不舒服，但现在好了。

 under way . through the water；in motion （said of a vessel starting out）（指船）在航行之中；在前进途中

The ship is under way for London．这艘船正在前往伦敦的途中。

 under way .  making progress or having started正在进行中；已开始

Preparations for the celebration of National Day are under way．庆祝国庆的准备工作正在进行之中。

Our plan is well under way．我们的计划正在顺利地实施之中。

up against . faced or confronted with面临；遭遇

In that type of business we will naturally be up against very stiff competition．在那类经营中，我们会自然遇到激烈的竞争。

We'll be up against a much stronger team．我们将面对的是一支强得多的队。

They were up against a lot of difficulties，but managed to overcome them．他们遇到了许许多多的困难，但还是设法克服了。

up against it . faced with a great difficulty or problem面临极大的困难；经济拮据

He is very resourceful，but this time he was up against it ．他一向足智多谋，可这次还是遇到了极大的困难。

My family is up against it because I can't find a job．由于找不到工作，我家经济拮据。

up and about . in good health；active after an illness病后康复；病后起床活动

It feels good to be up and about after a week of being indoors with the flu．患流感在家里呆了一周后，起床活动活动感觉挺好。

The heart operation restricted him to the hospital for several weeks，but now he's up and about and as active as ever．心脏病手术使他在医院呆了好几周，但是现在他已经康复而且象以前一样活跃了。

up and coming . alert；capable；smart机警；能干；聪明

Mr．Wang is one of the up and coming young men in our firm．王先生是我们公司里的能人之一。