9584.turbulence(名)湍流、乱流
The pilot announced that there was some turbulence ahead．
驾驶员预告说前方有乱流。

9585.turbulent(形)骚动的、骚乱的、动荡的；汹涌的
The current is turbulent.
水势汹涌。

9586.tumover(名)人员更替数、人员更换率
不可数
Why does your company have such a rapid turnover of staff?
贵公司人员变动为什么这么快？

9587.tutorial(形)个别指导的、家庭教师的；辅导的
With the increased number of students,it is quite usual for two or more students to attend a tutorial class together.
学生人数增多，两个或更多的学生一起上辅导课已是司空见惯。

9588.ultimatum(名)最后通牒
An ultimatum has been issued to him to with draw his troops from our territory.
向他提出的最后通牒是要求他把部队撤出我国领土。

9589.unassuming(形)谦虚的、不出风头的；保守的
I believe that a simple and unassuming life is good for everybody,physically and mentally.
我认为简单朴素、不张扬的生活方式对任何人的身心都有好处。

9590.unconventional(形)不符合习俗的、非常规的
His twin brother considered himself unconventional and original,so he set up as an artist．
他的孪生弟弟自以为卓然出众而又有创作天赋，因而成为了一名画家。

9591.undergraduate(名)大学生、大学肄业生
My brother is a Yale undergraduate.
我弟弟是耶鲁大学的大学生。

9592.underwear(名)内衣
单复数同形
She changes her underwear every day.
她每天换内衣。

9593.undulating(形)波浪起伏的、波动的
Their encircling and undulating movement contrasts pleasurably with the straight trunks of erect trees.
它们那种盘绕和波动的线条，和树木挺直的躯干形成了有趣的对比。

9594.unemployment(名)失业、失业状态
不可数
Miiilons of people were thrown into unemployment.
数百万人被迫失业。

9595.unfathomable(形)深不可测的、不可理解的
No more can I look into the depths of this unfathomable water.
我再也无法窥探这深不可测的水域奥秘了。

9596.union(名)工会、联盟、协会
He was compelled to join the union as a condition of getting the job．
获得该工作的先决条件是他被迫加入了工会。

9597.unprecedented(形)无先例的、空前的
The rate of growth was unprecedented.
这个成长率是前所未有的。

9598.unsound(形)不稳固的、不安全的
That bridge looks unsound to me．
依我看来那座桥不安全。

9599.upbringing(名)养育、教养、培养
不可数
He owed his success to the good upbringing he had．
他的成功归功于他受到的良好教养。

9600.upholstery(名)室内装潢品；室内装潢业
A sturdy ribbed fabric of wool,cotton,or wool and ootton,often with an embossed finish,are used for clothing and upholstery.
波纹织物是一种由羊毛、棉花和羊毛加棉花织成的结实织物，通常有凸起的图饰，用于制衣和室内装饰。

9601.upstage(动)抢某人的戏、抢……镜头
He upstage the other speaker by illustrating his talk with slides.
他演讲中配合幻灯片比其他演讲人更吸引听众。

9602.urban(形)都市的、城市的
同义词metropolitan
In some developing countries more and more people are migrating to urban areas．
在某些发展中的国家，越来越多的人向市区迁移。

9603.utensil(名)器皿、用具
This store sells cooking utensils．
这商店出售炊具。

9604.utility(名)公用事业；公用事业公司
I found that I had forgotten to pay the bills for utilities．
我发现忘了付水电及瓦斯的费用。

9605.vacancy(名)空缺、空职、空额
we have a vacancy for a computer programmer.
我们有一个电脑工程师的缺额。

9606.vaccine(名)牛痘苗、疫苗
This vaccine will give you immunity for two years.
接种这种疫苗可有两年的免疫力。

9607.vain(形)爱慕虚荣的；自负的、炫耀的
She's very vain about her good looks.
她为他那姣好的容貌而自负。

9608.valley(名)山谷；流域
The valley lay before us.
那山谷呈现在我们眼前。

9609.vehicle(名)运载工具；传播媒介
Language is the vehicle of human thought.
语言是人类表达思想的工具。

9610.vend(动)出售、贩卖
Elle vends ice cream．
艾拉赈卖冰淇淋。

9611.venomous(形)有毒的、分泌毒液的、有毒腺的
同义词toxic
A daddy longlegs spider is more venomous than a black widow, and it can open its mouth wide enough to bite a person．
成年长腿蜘蛛的毒性比黑寡妇还要毒，而且它的嘴可以张大到足以咬住人。

9612.ventilation(名)通风、空气流通
不可数
They altered the house to improve its ventilation.
他们把房子装修之后使它更通风。