1、倍數(shù)、分?jǐn)?shù)、小數(shù)與百分?jǐn)?shù)表示法 第1頁(yè)倍數(shù)A. 兩倍表示法a. twice表示兩倍：Twice nine is eighteen. 二九十八This box is twice as large as that one. 這個(gè)盒子是那個(gè)盒子兩個(gè)大。This box is twice larger than that one. 這個(gè)盒子比那個(gè)盒子大一倍。第2頁(yè)double表示兩倍The top-brand cigarettes are often sold at double the normal price here. 這里名牌香煙售價(jià)經(jīng)常比正常價(jià)高一倍。第3頁(yè)B. 三倍表示法triple n.

2、 三倍數(shù)Eighteen is the triple of six. 十八是六三倍 triple a. 三倍 a triple dose of medicine 三倍劑量藥 triple v. 增至三倍，使成三倍The farm tripled its profits last year. 農(nóng)場(chǎng)去年利潤(rùn)增至三倍His income tripled. 他收入增至三倍。第4頁(yè)C. 四倍表示法 a. quadruple n.80 is the quadruple of 20. 80是20四倍。b. quadruple a. 四倍The firm has an annual profit quadru

3、ple that of ours. 他們企業(yè)年度利潤(rùn)是我們四倍。c. quadruple v.（使）成四倍They quadrupled output to around 20 million tons他們把產(chǎn)量增至2,000萬噸左右，是原來四倍第5頁(yè)D. 多倍表示法a. 表示倍數(shù)用foldonefold 僅含一個(gè)，單一twofold a. & ad.兩倍（地）threefold a. & ad. 三倍（地）第6頁(yè)三以上倍數(shù)類推，即fourfold, fivefold, hundredfold等，其使用方法同twofold。比如：a twofold increase兩倍增加He repaid

4、the money twofold. 他加倍償還了那筆錢。The value of the house has increased fourfold since 1939. 房?jī)r(jià)自1939年以來增加了4倍。第7頁(yè)b. 表示三倍或三倍以上能夠用基數(shù)詞加 times at ten times normal speed以十倍于正常速度速度three times the size of是三倍大three times as large as比大兩倍Output of coal increased four times （或fourfold）. 煤產(chǎn)量增加了3倍。第8頁(yè)注意：以下同義句表示方式不一樣：GD

5、P (gross domestic product) was four times as great as that of last year. 國(guó)民生產(chǎn)總值是去年4倍。GDP (gross domestic product) was four times greater that of last year. 國(guó)民生產(chǎn)總值比去年增加了3倍。第9頁(yè)分?jǐn)?shù)A. 分?jǐn)?shù)組成 表示分?jǐn)?shù)時(shí)，分子須用基數(shù)詞，分母用序數(shù)詞。分子如是1以上，表示分母序數(shù)詞須用復(fù)數(shù)形式。以下表所表示： 1/3 a (one) third 2/3 two thirds3/5 three fifths第10頁(yè)B. 特殊分?jǐn)?shù)讀法a. 讀作a (one) half（不讀作one second）b. 讀作a (one) quarter 也能夠讀作a (one) fourthc. 百分?jǐn)?shù)讀法%讀作per cent5%讀作five per cent 0.5%讀作 (naught) point five per cent 第11頁(yè)d. 數(shù)學(xué)中可都用基數(shù)詞讀, 如：12讀作 one over two23讀作 two over three注意：復(fù)雜分?jǐn)?shù)多用此讀法，如：17/286讀作sevente