四. 在科技文章中，数字频繁出现，用阿拉伯数字比用单词陈述更有利。

Eg. The new engine has a capacity of 4.3 litres and a power out-put of 153 kilowatts at 4400 revolutions per minute.

这台新发动机的容积为4.3升，转速为每分钟4400转时输出功率是153千瓦。

Eg. We know that the weight of a cubic foot of air at 0oC and 76cm，pressure is 0.08l pound, or 12 cubic feet of air weigh a pound.

我们知道，1立方英尺的空气在0摄氏度和760毫米汞柱压力下，重量是0.81磅，也就是说12立方英尺空气的重量是1磅。

五. 句首不用阿拉伯数字，句末要尽量避免用阿拉伯数字。

Eg. 4th July is an important date in American history.

应该写成The fourth of July...

Eg. 19 couples took part in the ballroom dancing competition.

19对选手参加了交际舞比赛。

应改写成：Nineteen couples took...

Eg. 60％profit was a reported．

据报道有60％的利润。

应改写成：Sixty per cent profit…

Eg. 1345 kilograms force was applied at the center point of the bar.

试验时在杆的中点加1345公斤力。

可改成When tested, a force of l345 kg was applied...

六. 遇到分数，可用带连字符号的单词表示。

Eg. At 1east two-thirds of the class have had colds.

这个班至少有三分之二的学生患重感冒。

Eg. Nitrogen forms about four-fifths of the atmosphere.

氮约占大气的五分之四。