有关倍数增减的表达

倍数增加（2）
• Increase N times • Increase to N times • Increase by N times 增长到…倍 (or: x N) • Increase by a factor of N • N-fold increase in sth. Increase 常被raise, grow, go/step up, multiply等词替代 Eg. In 2004-5, 418 under-16-year-olds were referred to the Scottish drug misuse database (SDMD) compared with 106 in 1996-7. (Youth drug problems increase four-fold since 1997.)

倍数增加与减少的表达
倍数增加（1）
• A是B的N倍 A is N times as …as B A is N times …er than B A is N times the size/amount/length…of B
Eg. 小麦产量是水稻的两倍。 The output of wheat is twice as much as that of rice. Eg. 今年的出口比去年增加了一倍。 The export of this year is twice as much as what is was last year.
倍数增加（3）
• 表达两倍的特殊用法： A is as much (large, long…) again as B A is twice as much (large, long…) as B A is half as much (large, long…) again as B (=A is one and a half times as much as… B)
倍数增加（4）
• 翻倍与翻番： double triple，treble quadruple quintuple sextuple septuple
成两倍，翻一番 成三倍 成四倍，翻两番 成五倍 成六倍 成七倍
倍数减少
• A is N times as small (light, slow…) as B • A is N times smaller (lighter, slower…) than B • Decrease N times/N-fold • Decrease by N times/N-fold 减少到1/N (or:减少(N-1)/N ) • Decrease by a factor of N • a N-fold decrease/reduction Decrease 常被reduce, shorten, go/slow down等词替代 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. Eg. The equipment reduced the error probability by a factor of 5. 这种设备误差概念降低了4/5. Eg. When the voltage is stepped up by 10 times, the strength of the current is stepped down by 10 times. 每当电压升高9倍，电流强度便降低9/10.