The camshaft is a rotating shaft that has lobes , celled cams , opening and closing the intake and exhaust valves in time with the motion of the piston .When the cam pushes against the lifter , the lifter in tern pushes the valve open . When the cam rotates away from the lifter , the valve is closed by a spring that is attached to the valve . the camshaft must be synchronized with the crankshaft so that it makes one revolution for every two revolution of the crankshaft .this is a critical job, and can have a great impact on an engine’s performance at different speeds .
在活塞运动的同时，凸轮的旋转可以及时控制进气出气阀门的开启与关闭。当凸轮运动推动挺柱时，挺柱会有次序的推动阀门的开启。当凸轮旋转远离挺柱时，阀门上的弹簧会关闭阀门。凸轮轴必须与曲轴同步运转以保证曲轴每旋转两个周期凸轮轴旋转一个周期。这是一个关键性动作，并且对发动机性能在不同转速都会有很大影响。
Driving a car with a manual transmission, you depress the clutch, select a gear, and release the cultch while applying power to get the car to move. The clutch allows engine power to be applied gradually when a vehicle is starting out, and interrupts power to avoid gear crunching when shifting. Engaging the clutch allows power to transfer from the engine to the transmission and drive wheels. Disengaging the clutch stops the power transfer and allows the engine to continue turning without force to the drive wheels.
驾驶一辆带有手动变速器的汽车时，踩下离合器时，选择一个档位，当有能量输入时松开离合器使汽车运动。当发动汽车时发动机的功率会逐渐被传送到离合器，换挡时中断功率可以避免齿轮之间的摩擦声音。接合离合器，发动机的动率就会传送到变速器和驱动轮。松开离合器阻止能量的传送，并且发动机在没有能量输送到驱动轮的情况下还可以正常运转。
The rack-and-pinion gear-set does two things:
1 It converts the rotational motion of the steering wheel into the linear motion needed to turn the wheels.
2 It provides a gear reduction, making it easier to turn the wheels.
On most cars, it takes three to four complete revolutions of the steering wheel to make the wheels turn from lock to lock (from far left to far right) .
齿轮齿条齿轮组有两大功能：
1.把转向盘的旋转运动转变成直线运动来控制车轮。
2.可以使齿轮减速从而更便捷地控制车轮的转向。
对于大多数的汽车，转向盘的总回圈数（从最左边到最右边）需要3-4圈的完全旋转。
Oil is circulated through the engine by an oil pump. Most oil pumps have two small gears that mesh with each other. A pressure-regulator valve in the pump is used to prevent the lubrication system from reaching too high a pressure. The oil pump pulls oil up from the oil pan through the pick-up screen. The screen collects any large particles of dirt so that the oil entering the pump is fairly clean. The pump then directs the oil through an oil filter, which strains any remaining dirt out of the oil; the oil entering the engine lubrication passages should be clean.
机油在机油泵的作用下在发动机内循环流动。大多数机油泵有两个小齿轮来相互啮合。在泵里的调压阀阀门被用来阻止润滑系统达到高温。机油泵将机油通过机滤器吸上来。滤网可以过滤脏的小颗粒以保证进入到泵里的机油是完全清洁的。机油泵将剩下的比较脏的机油直接送到具有过滤功能的的机油滤清器内。机油进入发动机润滑系统就会是干净的了。
The following four steps show how the SRS airbag works:
1. In an impact, sensors in the car detect the sudden deceleration. If the crash is severe enough ,electricity flows to the inflator and causes ignition of the gas generator.
2. The gas generator then rapidly burns in the metal chamber .The rapid burning produces inert gases and amount of dust . The inert gases and dust are cooled and filtered during inflations of the airbag.
3. The inflating airbag splits open the trim cover .The airbag then rapidly unfolds and inflates in front of the occupant.
4. After inflation ,the gas is vented through opening or open weave areas in the airbag. These steps take place in a fraction of a second .Airbag deflate in under a second and may be pushed aside for occupants to exit.
以下四步是安全气囊的工作过程：
1.在碰撞中，汽车上的传感器感应到汽车的突然减速。如果不是很严重，电流会发出点火信号使气体发生器工作。
2.气体发生器会迅速在一个金属室内燃烧。迅速的燃烧便产生了许多惰性气体和大量灰尘。在安全气囊充气的同时这些惰性气体和灰尘会被冷却过滤。
3.充气的安全气囊会涨破装饰罩。安全气囊会迅速在乘客面前展开。
4.充气结束后，这些气体会从气囊的编制地方放出气体。这几步只发生在瞬间。安全气囊也会在瞬间放气可能还会把乘客推到外面。
In the case of a resistor, the voltage-current relationship is given by Ohm’s law, which states that the voltage across the resistor is equal to the current through the resistor multiplied by the value of the resistance. 就电阻来说, 电压—电流的关系由欧姆定律决定。欧姆定律指出:电阻两端的 电压等于电阻上流过的电流乘以电阻值。 2]It may be that the inductor voltage rather than the current is the variable of interest in the circuit. 或许在电路中,人们感兴趣的变量是电感电压而不是电感电流。 Viewed in this light, it will be found that the analysis of three-phase circuits is little more difficult than that of single-phase circuits. 这样看来,三相电路的分析比单相电路的分析难不了多少。 At unity power factor, the power in a single-phase circuit is zero twice each cycle. 在功率因数为 1时,单相电路里的功率值每个周波有两次为零。 It should be noted that if the polarity of point Awith respect to N ( is assumed for the positive half-cycle, then when used in the same phasor diagram should be drawn opposite to, or 180? out of phase with, . 应该注意,如果把 A 点相对于 N 的极性(定为正半周,那么在用于同一相量图中时就应该画得同相反,即相位差为 180? One problem with electronic devices corresponding to the generalized amplifiers is that the gains, AU or AI, depend upon internal properties of the two-port system. 对应于像广义放大器这样的电子装置,一个问题就是增益 AU 或者 AI ,它们取决于两输入端系统的内部特性。
Chapter 1 Passage 1 Human Body In this passage you will learn: 1. Classification of organ systems 2. Structure and function of each organ system 3. Associated medical terms To understand the human body it is necessary to understand how its parts are put together and how they function. The study of the body's structure is called anatomy; the study of the body's function is known as physiology. Other studies of human body include biology, cytology, embryology, histology, endocrinology, hematology, immunology, psychology etc. 了解人体各部分的组成及其功能，对于认识人体是必需的。研究人体结构的科学叫解剖学；研究人体功能的科学叫生理学。其他研究人体的科学包括生物学、细胞学、胚胎学、组织学、内分泌学、血液学、遗传学、免疫学、心理学等等。 Anatomists find it useful to divide the human body into ten systems, that is, the skeletal system, the muscular system, the circulatory system, the respiratory system, the digestive system, the urinary system, the endocrine system, the nervous system, the reproductive system and the skin. The principal parts of each of these systems are described in this article. 解剖学家发现把整个人体分成骨骼、肌肉、循环、呼吸、消化、泌尿、内分泌、神经、生殖系统以及感觉器官的做法是很有帮助的。本文描绘并阐述了各系统的主要部分。 The skeletal system is made of bones, joints between bones, and cartilage. Its function is to provide support and protection for the soft tissues and the organs of the body and to provide points of attachment for the muscles that move the body. There are 206 bones in the human skeleton. They have various shapes - long, short, cube - shaped, flat, and irregular. Many of the long bones have an interior space that is filled with bone marrow, where blood cells are made. 骨骼系统由骨、关节以及软骨组成。它对软组织及人体器官起到支持和保护作用，并牵动骨胳肌，引起各种运动。人体有206根骨头。骨形态不一，有长的、短、立方的、扁的及不规则的。许多长骨里有一个内层间隙，里面充填着骨髓，这即是血细胞的制造场所。 A joint is where bones are joined together. The connection can be so close that no movement is possible, as is the case in the skull. Other kinds of joints permit movement: either back and forth in one plane - as with the hinge joint of the elbow - or movement around a single axis - as with the pivot joint that permits the head to rotate. A wide range of movement is possible when the ball - shaped end of one bone fits into a socket at the end of another bone, as they do in the shoulder and hip joints. 关节把骨与骨连接起来。颅骨不能运动，是由于骨与骨之间的连接太紧密。但其它的关节可允许活动，如一个平面上的前后屈伸运动，如肘关节；或是绕轴心旋转运动，如枢轴点允许头部转动。如果一根骨的球形末端插入另一根骨的臼槽里，大辐度的运动（如肩关节、髋关节）即成为可能。 Cartilage is a more flexible material than bone. It serves as a protective, cushioning layer where bones come together. It also connects the ribs to the breastbone and provides a structural base for the nose and the external ear. An infant's skeleton is made of cartilage that is gradually replaced by bone as the infant grows into an adult. 软骨是一种比一般骨更具韧性的物质。它是骨连结的保护、缓冲层。它把肋骨与胸骨连结起来，也是鼻腔与内耳的结构基础。一个婴儿的骨骼就是由软骨组成，然后不断生长、
Veterinary Immunology and Immunopathology 141 (2011) 133–138 Contents lists available at ScienceDirect Veterinary Immunology and Immunopathology j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /v e t i m m Short communication Saccharomyces cerevisiae decreases in?ammatory responses induced by F4+enterotoxigenic Escherichia coli in porcine intestinal epithelial cells Galliano Zanello a ,b ,1,Franc ?ois Meurens a ,1,Mustapha Berri a ,Claire Chevaleyre a ,Sandrine Melo a ,Eric Auclair b ,Henri Salmon a ,? a Institut National de la Recherche Agronomique (INRA),UR1282,Infectiologie Animale et SantéPublique,F-37380Nouzilly (Tours),Indre et Loire,France b SociétéIndustrielle Lesaffre,Lesaffre Feed Additives,Marcq-en-Baroeul,France a r t i c l e i n f o Article history: Received 19October 2010Received in revised form 13December 2010 Accepted 31January 2011Keywords: Saccharomyces cerevisiae Enterotoxigenic Escherichia coli Pig Intestinal epithelial cells Cytokines Chemokines a b s t r a c t Probiotic yeasts may provide protection against intestinal in?ammation induced by enteric pathogens.In piglets,infection with F4+enterotoxigenic Escherichia coli (ETEC)leads to in?ammation,diarrhea and intestinal damage.In this study,we investigated whether the yeast strains Saccharomyces cerevisiae (Sc ,strain CNCM I-3856)and S.cerevisiae variety boulardii (Sb ,strain CNCM I-3799)decreased the expression of pro-in?ammatory cytokines and chemokines in intestinal epithelial IPI-2I cells cultured with F4+ETEC.Results showed that viable Sc inhibited the ETEC-induced TNF-?gene expression whereas Sb did not.In contrast,killed Sc failed to inhibit the expression of pro-in?ammatory genes.This inhibition was dependent on secreted soluble factors.Sc culture supernatant decreased the TNF-?,IL-1?,IL-6,IL-8,CXCL2and CCL20ETEC-induced mRNA.Furthermore,Sc culture supernatant ?ltrated fraction <10kDa displayed the same effects excepted for TNF-?.Thus,our results extended to Sc (strain CNCM I-3856)the inhibitory effects of some probiotic yeast strains onto in?ammation. ? 2011 Elsevier B.V. All rights reserved. 1.Introduction Enterotoxigenic Escherichia coli (ETEC)are pathogenic gram negative bacteria which infect humans and sev-eral species of farm animals such as calves and pigs.ETEC interacts with intestinal epithelial cells,colonizes the small intestine and secretes enterotoxins such as the heat-labile enterotoxins (LT),the heat-stable enterotox-ins (STa and/or STb),and the enteroaggregative E .coli heat-stable enterotoxin 1(EAST1)(Nagy and Fekete,2005).In pigs,ETEC infection and enterotoxin secretions can induce intestinal in?ammation and diarrhea resulting in reduced growth rate,increased mortality and economic ?Corresponding author.Tel.:+33247427331;fax:+33247427779.E-mail addresses:salmon@tours.inra.fr ,henri.salmon@tours.inra.fr (H.Salmon).1 These authors contributed equally to this work.loss (Fairbrother et al.,2005).Moreover,F4+ETEC strain induce pro-in?ammatory response in intestinal epithe-lial cells (Devriendt et al.,2010).Administration of the yeast Saccharomyces cerevisiae variety boulardii (Sb )has been shown to protect pigs in reducing ETEC transloca-tion (Lessard et al.,2009).In vitro studies showed that Sb secretes soluble factors that decrease the expression of pro-in?ammatory cytokines induced by enteric pathogens (Zanello et al.,2009).However,to our knowledge,there is no in vitro data regarding the anti-in?ammatory effects of S.cerevisiae (Sc )secreted soluble factors.Sc and Sb are members of the same species but they differ geneti-cally,metabolically and physiologically (Edwards-Ingram et al.,2007;Hennequin et al.,2001).Thus,in this study,we assessed if the non-commensal and non-pathogenic yeasts Sc (strain CNCM I-3856)and Sb (strain CNCM I-3799)secreted factors allowing the down-regulation of pro-in?ammatory gene expression in intestinal epithe-lial cells cultured with F4+ETEC.Sc (strain CNCM I-3856) 0165-2427/$–see front matter ? 2011 Elsevier B.V. All rights reserved.doi:10.1016/j.vetimm.2011.01.018
1) Electricity can be measured in amount and quality. 电可以用数量和质量来度量。 2) Instrument transformers are installed on the high-voltage equipment. 互感器安装在高压设备上。 3) Electric power is generated in power generating stations or plants. 电能是在发电站或发电厂产生的。 4) The meters are calibrated and the scale is designed to read the value of the desired unit. 这些仪表可以被校准并且设计了不同的量程，以便读出期望的数值。 5)Electrical energy can be stored in two metal plates separated by an insulation medium. Such a device is called a capacitor, and its ability to store electrical energy is termed capacitance. It is measured in Farads. 电能可以储存在被一绝缘介质隔开的两块金属板中，这样的装置被称为电容器，它储存电能的能力就被称为电容。电容的测量单位是法拉。 1)The signal should be filtered before it is amplified. The signal should be filtered before being amplified. 放大信号前，应先对其进行滤波。 2)An object becomes hot. It is placed in the sun. Once being placed in the sun, an object becomes hot. 物体放置在太阳下会变热。 3)We must do various experiments before a new electronic product is designed. Before designing a new electronic product we must do various experiments. 在设计一个新的电子产品之前，我们必须做各种实验。 4)Changing resistance is a method for controlling the flow of the current. 改变电阻是控制电流的一种方法。 5)Conducting electricity means the flow of electrons through an object. 传导电流意味着电子在物体内的流动。 1)The power supply, which is shown in block-diagram in Fig.1, is a single-phase switch-mode inverter. The power supply shown in block-diagram in Fig.1 is a single-phase switch-mode inverter. 图1中用框图表示的电源是一个单相开关逆变器。 2)A three-phase circuit, as it was pointed out above, is merely a combination of three single-phase circuits. A three-phase circuit, as pointed out above, is merely a combination of three single-phase circuits. 正如上面所指出的那样，三相电路只不过是三个单相电路的组合。 3) The transistor, which is working with correctly polarities, can work as an amplifier. The transistor working with correctly polarities can work as an amplifier. 工作于正确电源极性下的晶体管，作用就像放大器。 1）The capacity of individual generators is larger and larger so that the increasing demand of electric power is satisfied. The capacity of individual generators is larger and larger to satisfy the increasing demand of electric power. 单台发电机的容量越来越大，目的就是满足不断增长的用电需求。 2) What does a fuse do? It protects a circuit. The function of a fuse is to protect a circuit. 保险的作用就是保护电路。
1.Our big old house was closely related with the joys and sorrows of four generations. 2.I planted these roses a long, long time ago before your mother was born. 3.Many sons left home to fight against the Fascist Nazi. 4.Take the first friendly greeting and always keep it deep in your heart. 1.He has prepared answers to the questions that he expects to confront during the interview. 2.His sad story touched us so deeply that we nearly cried. 3.The two of them are walking hand in hand along the river bank, chatting, laughing, and looking happy. 4.When he heart the exciting news, tears of joy welled up in his eyes. 5.People from Shanghai can understand Suzhou dialect with ease, for Shanghai dialect and Suzhou dialect have much in common. 6.Henry and his wife are looking into the possibility of buying a new house within three years. 7.He finally gave in to his daughter’s repeated requests to further her education abroad. 8.We locked all our valuables away before we went on holiday. 9.Although we have parted from eah other, I hope that we will remain good friends and that we will care for and help each other just as we did in the past. 10.At that critical moment, the army commander summoned all the officers to work out new strategies and tactics which would make it possible to conquer the enemy. Unit 2 1.A gracious manner adds the greatest splendour to your image. 2.I firmly believed the note my guest sent me didn’t take long to write. 3.The simple phrase “Excuse me.” made most of your irritation disappear. 4.Being on time is a virtue which belongs not only to the past but also to the present. 5.Y ou shouldn’t accept the other person’s presence without thinking of its importance. 6.Good manners produce the same feelings or actions in others. 1.I am sorry I am late; I was at a meeting and couldn’t get away. 2.At the concert whnever a singer finished singing a beautiful song, the audience would burst into loud cheers to show their appreciation. 3.As a stylish dresser, she is always wearing stylish clothes, but she seldom cares about what she eats or drinks. 4.The nurse tells me that the doctors have done wonders for your heart disease. 5.When awarding the prize, the chairman complimented the winner on his great contribution to mankind. 6.This problem has bothered the experts for many years. 7.The crowd of demonstrators melted away when the police arrived. 8.Since punctuality is a good habit, we should pay much attention to it and make great efforts to cultivate this good habit. 9.The old man cherishes that girl, as if she were his own daughter. 10.It is just a routine physical checkup, nothing to get worried about.
第二部分 控制理论 第1章 1.1控制系统的引入 人类控制自然力量的设计促进人类历史的发展,我们已经广泛的能利用这种量进行在人类本身力量之外的物理进程?在充满活力的20世纪中,控制系统工程的发展已经使得很多梦想成为了现实?控制系统工程队我们取得的成就贡献巨大?回首过去,控制系统工程主要的贡献在机器人,航天驾驶系统包括成功的实现航天器的软着陆,航空飞机自动驾驶与自动控制,船舶与潜水艇控制系统,水翼船?气垫船?高速铁路自动控制系统,现代铁路控制系统? 以上这些类型的控制控制系统和日常生活联系紧密,控制系统是一系列相关的原件在系统运行的基础上相互关联的构成的,此外控制系统存在无人状态下的运行,如飞机自控驾驶,汽车的巡航控制系统?对于控制系统,特别是工业控制系统,我们通常面对的是一系列的器件,自动控制是一个复合型的学科?控制工程师的工作需要具有力学,电子学,机械电子,流体力学,结构学,无料的各方面的知识?计算机在控制策略的执行中具有广泛的应用,并且控制工程的需求带动了信息技术的与软件工程的发展? 通常控制系统的范畴包括开环控制系统与闭环控制系统,两种系统的区别在于是否在系统中加入了闭环反馈装置? 开环控制系统 开环控制系统控制硬件形式很简单,图2.1描述了一个单容液位控制系统, 图2.1单容液位控制系统 我们的控制目标是保持容器的液位h 在水流出流量V 1变化的情况下保持在一定 可接受的范围内,可以通过调节入口流量V 2实现?这个系统不是精确的系统,本系 统无法精确地检测输出流量V 2,输入流量V 1以及容器液位高度?图2.2描述了这 个系统存在的输入(期望的液位)与输出(实际液位)之间的简单关系, 图2.2液位控制系统框图 这种信号流之间的物理关系的描述称为框图?箭头用来描述输入进入系统,以及
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1. Civil engineering，the oldest of the engineering specialties，is the planning，design，construction, and management of the built environment．This environment includes all structures built according to scientific principles，from irrigation and drainage systems to rocket-launching facilities. 土木工程，最老的工程专业，是建筑环境的规划、设计、施工和管理。这个环境包括从灌溉和排水系统到火箭发射设施的所有根据科学原理建造的结构物。 2. Civil engineers build roads，bridges，tunnels，dams，harbors，power plants，water and sewage systems，hospitals，schools，mass transit，and other public facilities essential to modern society and large population concentrations． 土木工程师修建道路、桥梁、隧道、大坝、港口、发电站、水系统和污水系统，医院、学校、公共交通系统，以及现代化社会和大量人口集中的地方所必需的其他公共设施。 3. Computers are a necessity for the modern civil engineer because they permit the engineer to efficiently handle the large quantities of data needed in determining the best way to construct a project． 计算机对于现代土木工程师而言是必不可少的，因为它们可使工程师高效地处理大量数据，这些数据是在确定最优施工方案时所需要的。 4. They also determine the combination of appropriate materials：steel，concrete，plastic，stone，asphalt，brick，aluminum，or other construction materials． 他们还确定适当的材料组合：钢材、混凝土、塑料、石料、沥青、砖、铝或其他的建筑材料。 5. In this branch of civil engineering, engineers build pipelines and related facilities which transport liquids, gases, or solids ranging from coal slurries (mixed coal and water) and semiliquid wastes, to water, oil, and various types of highly combustible and noncombustible gases. 在土木工程的这个分支里，工程师修建运输液体、气体或固体的管道和相关的设施，运输的物质范围从煤浆和半液体废料到水、石油和不同类型的高燃性和非燃性气体。 6. They coordinate the activities of virtually everyone engaged in the work：the surveyors；workers who lay out and construct the temporary roads and ramps，excavate for the foundation，build the forms and pour the concrete；and workers who build the steel framework．These engineers also make regular progress reports to the owners of the structure． 事实上，他们协调工程中每个人的活动：勘测员、为临时道路和斜坡定线和施工、挖基础、建模和浇注混凝土的工人、以及绑扎钢筋的工人。这些工程师还为建筑业主定期提供进度报告。 7. This art includes，in addition to buildings，all the civil engineering structures such as dams，canals，tunnels，aqueducts，and bridges．
Fashion,which is as old as time and as new as tomorrow,is one of the most powerful forces in our lives .It influences what we wear,the way we talk,the foods we eat,the way we live,how and where we travel,what we travel,what we look at,and what we listen to.Fashion is what lead us todiscard a product that is still useful but is no longer ―in‖.It is also what makes us sometimes wear more clothes than we may actually need,and sometimes less than is needed to product us from the ccold or the sun. 流行是这样一种事物，是我们抛弃了还可以使用，但不再时髦的产品。有时候使我们穿比我们真正穿的衣服多，有时候比我们穿抵御严寒酷暑的少。 If there is one absolute constant pertaining to fashion,it is the fact that it is always changing-sometimes rapidly,sometimes slowly,but it is never static or dormant.This element of change is recognized in the definitions of fashion itself cited earlier,by the use of such words as ―prevailing‖or ―a given period of time.‖To ignore the element of change is like looking at a still photograph in place of a motion picture.The still tells you what is happening here and now ;the motion picture shows you what came before and what may lie ahead. 如果存在着一种符合流行的绝对永恒，那就是流行是永远变化着的这一事实，（这种变化）时快时慢，但绝不会固定下来或呈休止状态。 “Fashion is a social phenomenon which reflects the same continuing change that rides through any given age .‖Change in fashion ,he emphasized,‘correspond with the subtle and often hidden network of forces that operate on society……’ “流行是一种社会现象，它反映了任何特定年代同样都要经历的持续变化。‖他强调说：“流行变迁与那些作用于社会的影响力量所具有的微妙，而又常常是暗藏着的系统是一致的。”It is only in restrospect that fashion changes seem marked or sudden .Autually ,they come about as a result of a series of gradual shifts from one season to the next.For example ,when women’s skirts began inching up from midcalf in the 1960s,this gradual shortening was not particularly noticeable at first .It was only when skirts moved thigh-high,in the form of minis and micro-minis ,that people took notice of the approaching extreme.Similarly,when men begin to abandon ultrannarrow ties and suit lapels in favor of more and more width,the changs are not noticed at first. 只有当追溯过去的时候，流行的变迁才显得特别引人注目或突然，实际上，这些变迁的发生是从一个季节到另一个季节的一系列逐渐变化的结果。例如，女裙的逐渐变短的时候并没有被注意到，。 ………………………………………………………… Color can be the basis for a whole group or line .It is the first element to which consumers respond .People relate personally to color,usually either selecting or rejecting a garment beccause of its ccolor appeal.Therefore,designers must cconsider their customers and provide colors that are both appealing and flattering. 色彩是整个款式系列中的基本要素，它是能够引起顾客回应的第一要素。人们把色彩和个人联系起来，他们往往根据颜色来选择或拒绝一件衣服，因此设计师必须考虑他们的顾客，并且提供出令他们喜爱和满意的色彩，消费群体。 In clothing,neutrals such as beige,tan,brown,white ,gray,and black are even more popular than the ccolors just mentioned.The reason is probably that they present a pleasing background for the wearer without completing for attention. Neutrals are part of every season‖s fashion picture ,as either a strong fashion statement or a way to round out a color story. 在服装中，中色调例如灰中色，深褐，褐色，白灰和黑色，甚至还有比刚刚提到的更多的