,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,科技英语的语言结构特点,科技英语注重科学性、逻辑性、正确性和严密性，它除具有语言标准、语气正式、文体质朴、陈述客观、逻辑严密、专业性强这些文体特征外，在词汇、语法这些语言结构方面科技英语也有其自身的特点。,1词汇特点,(1)习惯使用复合词与缩略词,Miniultrasonicprober=mini+ultra+sonic+prober(微型超声波金属探测仪),Pseudophotoesthesia=pseudo+photo+esthesia(光幻觉),CAD=computer-aided+design(计算机辅助设计),(2)大量使用名词化结构,If,after a body is deformed by some force,it returns to its original shape or size after removal of the force,the material is said to be elastic,如果某一物体在力的作用下产生变形，去除作用力之后，又能恢复原来的形状和大小，那么这物体就称为弹性物体。,The compression of the soil under the applied stresses would force some water out of the voids,施加压力压缩土壤会使一些水从孔隙中排出。,An important part of preliminary structural design is the selection of the structural system with consideration given to its relationship to construction economics,初步结构设计的一个重要局部是选择结构体系，同时考虑它与建筑经济学的关系。,2语法特点,(1)频繁使用非限定动词,Termed hydraulic cements because they react with water,the cements have the ability to harden under water,因为这种水泥与水反响，故称为水硬性水泥，这种水泥在水下也能够硬化。,The momentcurvature relationship chosen is assumed to have a horizontal branch beyond yield,with the moment remaining constant at the ultimate value,所选用的弯矩-曲率关系是假定超过屈服后有一个水平段，即弯矩保持在极限值不变。,非限定动词 英语上根据动词在句法上是否受到主语的限定，英语动词又可以分为限定动词(Finite Forms of Verbs)和非限定动词(Non-Finite Forms of Verbs)。非限定动词，又叫非谓语动词，在句中不能单独充当谓语但可以和情态动词或助动词一起充当谓语，它们不受主语的限定，没有人称和数的变化，具有名词、形容词和副词的特征，在句中可以充当主语、宾语、表语、定语、状语、补足语等。同时非限定动词也保存了动词的局部特征，有时态和语态的变化，也可以有自己的宾语、表语、状语等，构成非限定动词短语，在逻辑意义上也有其动作的执行者或承受者，叫非限定动词的逻辑主语(Logical Subjects)。英语非限定动词有三种根本形式：不定式(Infinitives)、动名词gerund、分词现在分词Present Participle和过去分词ed Participles)。,(2)广泛使用被动语态,Structural connections between steel members are often made by arcwelding techniques,钢构件间的结构连接常用弧焊技术来实现。,The structural failure of the foundation may occur if the foundation itself is not Properly designed to sustain the imposed stresses,如果根底本身未能正确设计以承受施加的应力，根底就可能产生结构破坏。,(3)经常使用长句,Although this method is more commonly used in the construction of silos,grain elevators,bridge piers,and other heavy structures,it lends itself at times to the construction of elevator and stair shafts usually found as part of the service core in high一 rise office or apartment buildings,这种方法通常用于筒仓、粮仓、桥墩和其他重型结构，有时也适用于高层办公楼或公寓楼中作为公共设施局部的电梯井和楼梯间的施工。,Some typical examples of buildings using the cantilever principle demonstrate that the concept is not only found on the smaller scale of overhanging eaves and cantilevered balconies,but also on the medium scale to support buildings because of unfavorable site conditions as well as on the large scale for roofs of stadiums and hangars because of functional necessity,一些利用悬挑原理的典型建筑例子说明悬挑概念不仅适用于小型的悬挑屋檐、悬挑阳台，而且适用于因场地条件不利而设计的用来支撑中型建筑的屋面，以及因功能需要而设计的大型体育场馆和飞机库的屋面。,谢谢！,