在漢英筆譯和英語(yǔ)寫(xiě)作中，經(jīng)常會(huì)遇到數(shù)字；哪些場(chǎng)合用單詞表示，哪些場(chǎng)合用阿拉伯?dāng)?shù)字表示，往往使人難以確定，現(xiàn)行語(yǔ)法書(shū)中也極少涉及此類問(wèn)題。
 
　　實(shí)際上，以英語(yǔ)為母語(yǔ)的國(guó)家，在書(shū)寫(xiě)數(shù)字時(shí)已形成幾條約定俗成的規(guī)則，現(xiàn)總結(jié)如下供讀者參考。
 
1 英美等國(guó)的出版社在排版時(shí)遵循一條原則，即1至10用單詞表示，10以上的數(shù)目用阿拉伯?dāng)?shù)字（也有的以100為界限），這條原則值得我們行文時(shí)借鑒。如：

That table measures ten feet by five. 那個(gè)工作臺(tái)長(zhǎng)10英尺，寬5英尺。

The traditional pattern of classroom experience at the college level brings the professor and a group of 20 to 30 students together for a 45-to-50-minute class session two or three times a week.
由一個(gè)教授和十名學(xué)生每周會(huì)晤兩三次，每次授課時(shí)間45到50分鐘，是大學(xué)程度課堂教學(xué)的傳統(tǒng)方式。

2 大數(shù)目用阿拉伯?dāng)?shù)字表示顯得更簡(jiǎn)潔明了，但不定數(shù)量、近似值用單詞表示較恰當(dāng)。如：

There are 203817 voters on the electoral rolls。選舉名單上有203817個(gè)投票人。

Nearly thirty thousand voters took part in this election.
近3萬(wàn)個(gè)投票人參加了這次選舉。

3 遇到日期、百分比、帶單位的特殊數(shù)字，通常用阿拉伯?dāng)?shù)字。如：

Maximum swivel of table is l20. 工作臺(tái)的最大回轉(zhuǎn)角度是120度。

①3rd march l991或3 march l991; a discount of 5 percent（5%的折扣）;
②purchased 7 yards of carpet（買(mǎi)7碼地毯）;
③ordered 2 pounds of minced steak （訂購(gòu)2磅剁碎的肉）.

如果涉及的數(shù)目和單位是不定數(shù)，可用單詞表示。
如：① about five miles per hour（每小時(shí)大約5英里）;
②at least ten yards away（至少有10碼遠(yuǎn)）;
③hesitated for a moment or two（猶豫了片刻）;
④i have warned you a hundred times（我已經(jīng)警告你多少遍了）.

4 在科技文章中，數(shù)字頻繁出現(xiàn)，用阿拉伯?dāng)?shù)字比用單詞陳述更有利，如：

The new engine has a capacity of 4.3 liters and a power out-put of 153 kilowatts at 4400 revolutions per minute。
這臺(tái)新發(fā)動(dòng)機(jī)的容積為4.3升，轉(zhuǎn)速為每分鐘4400轉(zhuǎn)時(shí)輸出功率是153千瓦。

we know that the weight of a cubic foot of air at 0℃，and 76cm，pressure is 0.08l pound, or 12 cubic feet of air weigh a pound.
我們知道，1立方英尺的空氣在0攝氏度和760毫米汞柱壓力下，重量是0.81磅，也就是說(shuō)12立方英尺空氣的重量是1磅。

5 句首不用阿拉伯?dāng)?shù)字，句末要盡量避免用阿拉伯?dāng)?shù)字。

4th July is an important date in American history. 應(yīng)該寫(xiě)成the fourth of July...

19 couples took part in the ballroom dancing competition. 19對(duì)選手參加了交際舞比賽。應(yīng)改寫(xiě)成：Nineteen couples took...

60% profit was a reported．據(jù)報(bào)道有60%的利潤(rùn)。應(yīng)改寫(xiě)成：Sixty per cent profit...

1345 kilograms force was applied at the center point of the bar. 試驗(yàn)時(shí)在桿的中點(diǎn)加1345公斤力?？筛某?/span>When tested, a force of l345 kg was applied...

6 遇到分?jǐn)?shù)，可用帶連字符號(hào)的單詞表示，如：

At 1east two-thirds of the class have had colds. 這個(gè)班至少有三分之二的學(xué)生患重感冒。

Nitrogen forms about four-fifths of the atmosphere. 氮約占大氣的五分之四。