英语语法：倍数的表达方法和译法
导语：英语表示倍数增减或倍数对比的句型多种多样，英汉两语在表述或对比倍数方面存在着语言与思维差异。下面是小编为您收集整理的关于英语倍数的表达方法和译法，欢迎阅读!
英语倍数的用法：倍数减少
(一)A is n times as small (light, slow, ...) as B. ⑿
A is n times smaller (lighter, slower, ...) than B. ⒀
以上两句均应译为：A的大小(重量、速度、……)是B的1/n，或A比B小(轻、慢、……)(n-1)/n。
eg: The hydrogen atom is nearly 16 times as light as the oxygen atom.
氢原子的重量约为氧原子的1/16(即比氧原子约轻15/16)。
eg: This sort of membrane is twice thinner than ordinary paper.
这种薄膜比普通纸张要薄一半(即是普通纸厚度的1/2)。
注：当相比的对象B很明显时，than/as B 常被省去。
(二)decrease n times / n-fold ⒁
decrease by n times ⒂
decrease by a factor of n ⒃
以上三句均译为：减少到1/n，或减少(n-1)/n。decrease常被reduce、shorten、go/slow down 等词替代。
eg: Switching time of the new-type transistor is shortened 3 times.
新型晶体管的`开关时间缩短到1/3(即缩短了2/3)。
eg: When the voltage is stepped up by ten times, the strength of the current is stepped down by ten times.
电压升高9倍，电流强度便降低9/10(即降低90%)。
eg: The equipment reduced the error probability by a factor of 5.
该设备误差概率降低了4/5。
(三)There is a n-fold decrease / reduction... ⒄
应译为：减至1/n，或减少(n-1)/n。
这个句型还有其它一些形式，
eg: A rapid decrease by a factor of 7 was observed.
发现迅速减少到1/7。
eg: The principal advantage of the products is a two-fold reduction in weight.
这些产品的主要优点是重量减轻了1/2。
从以上倍数增减句型及其译法中不难看出：与汉语不同的是，英语在表述或比较倍数时，无论使用什么句型(除了不含倍数词的again句型外)都包括基础倍数在内，因此都不是净增或净减n倍，而是净增或净减n-1倍。所以句型 ⑶、⑸ 表示的倍数增量=句型 ⑷;句型 ⒀ 表示的倍数比差=句型 ⑿，且decrease (by) 3 times应译为“减少2/3”，而不是“减少3/4”。
增加，减少，分别怎么翻译，都明白了吗?弱国还有什么不清楚的，多看看例句，或者自己造句翻译。这样可以使我们掌握得更好。
英语倍数的用法：倍数增加
(一)A is n times as great (long, much, ...) as B. ⑴
A is n times greater (longer, more, ...) than B. ⑵
A is n times the size (length, amount, ...) of B. ⑶
以上三句都应译为：A的大小(长度、数量、……)是B的n倍，或A比B大(长、多、……)n-1倍。
eg: This book is three times as long as that one. / three times longer than that one. / three times the length of that one.
这本书的篇幅是那本书的3倍(即比那本书长两倍)。
注：当相比的对象B很明显时，than (as, of) B 常被省去。
(二)increase to n times ⑷
increase n times / n-fold ⑸
increase by n times ⑹
increase by a factor of n ⑺
以上四句均应译为：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.
集成电路的产量比去年增加了两倍。
eg: The output of chemical fertilizer has been raised five times as against 1986.
化肥产量比1986年增加了4倍。
eg: That can increase metabolic rates by two or three times.
那可使代谢率提高到原来的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.
漏电压增加了3倍(即增加到原来的4倍)。
注：在这类句型中increase常被raise、grow、go/step up、multiply 等词所替代。
(三)There is a n-fold increase / growth... ⑻
应译为：增加n-1倍，或增至n倍。
这个句型还有其它一些形式：
eg: A record high increase in value of four times was reported.
据报道，价值破记录地增长了3倍。
(四)double(增加1倍)、treble(增加2倍)、quadruple(增加3倍)⑼
eg: The efficiency of the machines has been more than trebled or quadrupled.
这些机器的效率已提高了2倍或3倍多。
(五)此外，英语中还有一种用again而不用倍数词来比较倍数的方法，如：
A is as much (large, long, ...) again as B. = A is twice as much (large, long, ...) as B. ⑽
应译为：A比B多(大、长、……)1倍。
A is half as much (large, long, ...) again as B. = A is one and a half times as much (large, long, ...) as B. ⑾
应译为：A比B多(大、长、……)一半，即A是B的一倍半。
