非限定動詞
如前所述，科技文章要求行文簡練，結(jié)構(gòu)緊湊，為此，往往使用分詞短語代替定語從句或狀語從句；使用分詞獨(dú)立結(jié)構(gòu)代替狀語從句或并列分句；使用不定式短語代替各種從句；介詞十動名詞短語代替定語從句或狀語從句。這樣可縮短句子，又比較醒目。
試比較下列各組句子。
A direct current is a current flowing always in the same direction.
直流電是一種總是沿同一方向流動的電流。
Radiating from the earth, heat causes air currents to rise.
熱量由地球輻射出來時，使得氣流上升。
A body can more uniformly and in a straight line,there being no cause to change that motion.
如果沒有改變物體運(yùn)動的原因，那么物體將作勻速直線運(yùn)動。
Vibrating objects produce sound waves ,each vibration producing one sound wave.
振動著的物體產(chǎn)生聲波，每一次振動產(chǎn)生一個聲波。
In communications, the problem of electronics is how to convey information from one place to another.
在通訊系統(tǒng)中，電子學(xué)要解決的問題是如何把信息從一個地方傳遞到另一個地方。
Materials to be used for structural purposes are chosen so as to behave elastically in the environmental conditions.
結(jié)構(gòu)材料的選擇應(yīng)使其在外界條件中保持其彈性。
There are different ways of changing energy from one form into another.
將能量從一種形式轉(zhuǎn)變成另一種形式有各種不同的方法。
In making the radio waves correspond to each sound in turn, messages are carried from a broadcasting station to a receiving set.
使無線電波依次對每一個聲音作出相應(yīng)變化時，信息就由廣播電臺傳遞到接收機(jī)
如前所述，科技文章要求行文簡練，結(jié)構(gòu)緊湊，為此，往往使用分詞短語代替定語從句或狀語從句；使用分詞獨(dú)立結(jié)構(gòu)代替狀語從句或并列分句；使用不定式短語代替各種從句；介詞十動名詞短語代替定語從句或狀語從句。這樣可縮短句子，又比較醒目。
試比較下列各組句子。
A direct current is a current flowing always in the same direction.
直流電是一種總是沿同一方向流動的電流。
Radiating from the earth, heat causes air currents to rise.
熱量由地球輻射出來時，使得氣流上升。
A body can more uniformly and in a straight line,there being no cause to change that motion.
如果沒有改變物體運(yùn)動的原因，那么物體將作勻速直線運(yùn)動。
Vibrating objects produce sound waves ,each vibration producing one sound wave.
振動著的物體產(chǎn)生聲波，每一次振動產(chǎn)生一個聲波。
In communications, the problem of electronics is how to convey information from one place to another.
在通訊系統(tǒng)中，電子學(xué)要解決的問題是如何把信息從一個地方傳遞到另一個地方。
Materials to be used for structural purposes are chosen so as to behave elastically in the environmental conditions.
結(jié)構(gòu)材料的選擇應(yīng)使其在外界條件中保持其彈性。
There are different ways of changing energy from one form into another.
將能量從一種形式轉(zhuǎn)變成另一種形式有各種不同的方法。
In making the radio waves correspond to each sound in turn, messages are carried from a broadcasting station to a receiving set.
使無線電波依次對每一個聲音作出相應(yīng)變化時，信息就由廣播電臺傳遞到接收機(jī)