現將常用的英語倍數句型及其正確譯法歸納如下：
倍數增加
(一) A is n times as great(long，much，…)as B.(①)
A is n times greater (longer， more，…)than B.(②)
A is n times the size (length， amount，…)of B.(③)
以上三句都應譯為;A的大小(長度，數量，……)是B的n倍[或A比B大(長，多，……)n-1倍].
Eg. This book is three times as long as (three times longer than，three times the length of )that one. 這本書的篇幅是那本書的3倍(即長兩倍)。
註：當相比的對象B很明顯時，than(as，of)B常被省去。
(二)increase to n times(④)
increase n times/n-fold(⑤)
increase by n times(⑥)
increase by a factor of n(⑦)
以上四式均應譯為：增加到n倍(或：增加n-1倍)。
Eg. The production of integrated circuits has been increased to three times as compared with last year. 集成電路的產量比去年增加了兩倍。
Eg. The output of chemical fertilizer has been raised five times as against l986. 化肥產量比1986年增加了4倍。
Eg. That can increase metabolic rates by two or three times. 那可使代謝率提高到原來的2倍或3倍(即提高1倍或2倍)。
Eg. The drain voltage has been increased by a factor of four. 漏電壓增加了3借(即增加到原來的4倍)。
註：在這類句型中increase常被raise，grow，go/step up，multiply等詞所替代。
(三)There is a n-fold increase/growth…(⑧) 應譯為：增加n-倍(或增至n倍)。這個句型還有其它一些形式：
Eg. A record high increase in value of four times was reported. 據報導,價值破記錄地增長了3倍。
(四)double (增加1倍)，treble(增加2倍)，quadruple(增加3倍)。(⑨)
Eg. The efficiency of the machines has been more than trebled or quadrupled. 這些機器的效率已提高了2倍或3倍多。
(五)此外，英語中還有一種用again而不用倍數詞來比較倍數的方法，
如： A is as much (large，long，…)again as B.(= A is twice as much (large，long，…)as B.(⑩)應譯為：A比B多(大，長，……)1倍。
A is half as much (large， 1ong，…)again as B. 【= A is one and a half times as much (large， 1ong，…)as B.】(11) 應譯為:A比B多(大，長……)一半(即A是B的一倍半)。
倍數減少
(一)A is n times as small (light，slow，…)as B.(12)
A is n times smaller (lighter， slower，…) than B.(13)
以上兩句均應譯為：A的大小(重量，速度，……)是B的1/n[或A比B小(輕，慢，……)(n-1)/n]。
Eg. The hydrogen atom is near1y l6 times as light as the oxygen atom. 氫原子的重量約為氧原子的1/16(即比氧原子約輕15/16)。
Eg. This sort of membrane is twice thinner than ordinary paper. 這種薄膜比普通紙張要薄一半(即是普通紙厚度的1/2)。
註：當相比的對象B很明顯時，than/as B常被省去。
(二)decrease n times/n--fold (14)
decrease by n times(15)
decrease by a factor of n(16)
以上三式均譯為：減少到1/n[或：減少(n-1)/n]。 decrease常被reduce， shorten， go/slow down等詞替代。
Eg. Switching time of the new-type transistor is shortened 3 times. 新型電晶體的開關時間縮短了1/3(即縮短到2/3)。
Eg. When the voltage is stepped up by ten times， the strength of the current is stepped down by ten times. 電壓升高9倍，電流強度便降低9/10(即90%)。
Eg. The equipment reduced the error probability by a factor of 5. 該設備誤差概率降低了4/5。
(三)There is a n-fold decrease/reduction… 應譯為：減至1/n [或：減少(n一1)/n]。(17) 這個句型還有其它一些形式，
Eg. A rapid decrease by a factor of 7 was observed. 發現迅速減少到1/7。
Eg. The principal advantage of the products is a two-fold reduction in weight. 這些產品的主要優點是重量減輕了1/2。
從上列倍數增減句型及其譯法中不難看出：與漢語不 同的是，英語在表述或比較倍數時，無論使用什麼句 型(除了不含倍數詞的again句型外)都包括基礎倍 數在內，因此都不是淨增或淨減n倍，而是淨增或 淨減n-1倍。所以句型⑤、③表示的倍數增量=句型④; 句型(13)表示的倍數比差=句型12，且decrease(by) 3 times應譯為「減少2/3」，而不是「減少3/4」。