4. Vibrating objects produce sound waves, each vibration producing one sound wave 振动着的物体产生声波,每一次振动产生一个声波。 5. In communications, the problem of electronics is how to convey information from one place to another 在通讯系统中,电子学要解决的问题是如何把信息从一个地方传递到另一个地方 Is to be used for structural purposes are chosen so as to behave elastically in the environmental conditions 结构材料的选择应使其在外界条件中保持其弹性, 7. There are different ways of changing energy from one form into another. 将能量从一种形式转变成另一种形式有各种不同的方法, 8. In making the radio waves correspond to each sound in turn, messages are carried from a broadcasting station to a receiving set 使无线电波依次对每一个声音作出相应变化时,信息就由广播电台传递到接收机。 (四)后置定语 大量使用后置定语也是科技文章的特点之一。常见的结构有以下五种: 1.介词短语 The forces due to friction are called frictional forces 由于摩擦而产生的力称之为摩擦力 A call for paper is now being issued 征集论文的通知现正陆续发出 2.形容词及形容词短语 In this factory the only fuel available is coal 该厂唯一可用的燃料是煤 In radiation, thermal energy is transformed into radiant energy, similar in nature to 热能在辐射时,转换成性质与光相似的辐射能。 3.副词 The air outside pressed the side in 外面的空气将桶壁压得凹进去了 The force upward equals the force downward so that the balloon stays at the level 向上的力与向下的力相等,所以气球就保持在这一高度 4.单个分词,但仍保持校强的动词意义 The results obtained must be checked 获得的结果必须加以校核 The heat produced is equal to the electrical energy wasted 产生的热量等于浪费了的电能。 5.定语从句 During construction, problems often arise which require design changes 在施工过程中,常会出现需要改变设计的问题6 4．Vibrating objects produce sound waves, each vibration producing one sound wave. 振动着的物体产生声波，每一次振动产生一个声波。 5．In communications, the problem of electronics is how to convey information from one place to another. 在通讯系统中，电子学要解决的问题是如何把信息从一个地方传递到另一个地方。 6．Materials to be used for structural purposes are chosen so as to behave elastically in the environmental conditions. 结构材料的选择应使其在外界条件中保持其弹性。 7．There are different ways of changing energy from one form into another. 将能量从一种形式转变成另一种形式有各种不同的方法。 8．In making the radio waves correspond to each sound in turn, messages are carried from a broadcasting station to a receiving set. 使无线电波依次对每一个声音作出相应变化时，信息就由广播电台传递到接收机。 （四）后置定语 大量使用后置定语也是科技文章的特点之一。常见的结构有以下五种： 1．介词短语 The forces due to friction are called frictional forces. 由于摩擦而产生的力称之为摩擦力。 A call for paper is now being issued. 征集论文的通知现正陆续发出。 2．形容词及形容词短语 In this factory the only fuel available is coal. 该厂唯一可用的燃料是煤。 In radiation, thermal energy is transformed into radiant energy, similar in nature to light. 热能在辐射时，转换成性质与光相似的辐射能。 3．副词 The air outside pressed the side in. 外面的空气将桶壁压得凹进去了。 The force upward equals the force downward so that the balloon stays at the level. 向上的力与向下的力相等，所以气球就保持在这一高度。 4．单个分词，但仍保持校强的动词意义 The results obtained must be checked. 获得的结果必须加以校核的 The heat produced is equal to the electrical energy wasted. 产生的热量等于浪费了的电能。 5．定语从句 During construction, problems often arise which require design changes. 在施工过程中，常会出现需要改变设计的问题