如前所述，科技文章要求行文简练，结构紧凑，为此，往往使用分词短语代替定语从句或状语从句；使用分词独立结构代替状语从句或并列分句；使用不定式短语代替各种从句；

介词十动名词短语代替定语从句或状语从句。

这样可缩短句子，又比较醒目。试比较下列各组句子。
A direct current is a current flowing always in the same direction.

直流电是一种总是沿同一方向流动的电流。
Radiating from the earth, heat causes air currents to rise.

热量由地球辐射出来时，使得气流上升。
A body can more uniformly and in a straight line,there being no cause to change that motion.

如果没有改变物体运动的原因，那么物体将作匀速直线运动。
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。
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。
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。
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。
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。