倍数的表达方法(附练习及答案).doc

“倍数”的常用表达方式
一、 用 times 表示倍数（一般限于包括基数在内三倍或三倍以上的数。表示两倍的数，一般用 twice ）。其句式有：
1. “… times ＋形容词 / 副词的比较级＋ than …”例如：
Line AB is three times longer than line CD. 线段 AB 是（线段） CD 的三倍长。
This hall is five times bigger than our classroom. 这个大厅比我们的教室大 5 倍。
2. “… times +as + 形容词 / 副词的原级＋ as …”例如：
This table is three times as long as that one. 这张桌子是那张桌子的三倍长。
This dictionary is five times as thick as the one you borrowed from the library.
这本词典的厚度是你从图书馆借的那本（厚度）的 5 倍。
3. “… times + the + 名词（如： size， height， weight， length， width 等）＋ of …”例如：
The earth is 49 times the size of the moon. 地球的体积是月球的 49 倍。
This river is three times the depth of that one. 这条河是那条河的三倍深。
4. “… times + more ＋名词＋ than …”例如：
He earns five times more money than he did ten years ago. 他现在挣的钱比十年前挣的多 5 倍。
There are twice more students in our class than in theirs. 我们班的学生人数比他们班多两倍
5. “… times +as many （或 much ）＋名词＋ as …”例如：
We've produced twice as much cotton this year as （ we did ） ten years ago.
今年我们生产的棉花比十年前多了一倍。（汉语中的多一倍实际上也指两倍一样多。）
He has got three times as many books as his sister. 他拥有的书的数量是他妹妹的 3 倍。
6. “… times + what 从句”例如：
The length of the road is four times what it was three years ago. 这条路的长度是三年前的 4 倍。
The price of the meat is twice what it was last year. 肉价是去年的两倍。
7.  “… times + up on （或 over ）…”例如：
The size of the sun is a million times over that of the earth. 太阳的体积比地球的体积大一百万倍。
He is three times up on your age. 他的年龄是你的4倍（或：比你的年龄大3倍）。
8. “… +by + … times ”例如：
Compared with last year， our coal output has increased by three times. 与去年相比，我们的煤产量增长了3倍。
His speed is faster than mine by four times. 他的速度比我的快 4 倍。
9. “… times + compared with ＋被比较对象”例如：
The number of the students in our school has increased for times compared with 1980.
我们学校的学生人数比 1980 年增加了3倍。
10. “… times + that of + 被比较对象”例如：
In this workshop the output of July was 3.5 times that of January. 这个车间七月份的产量是元月份的 3.5 倍。
二、用分数、百分数表示倍数。例如：
The box is one-third bigger than that one. 这个盒子比那个盒子大三分之一。
Last year the output value of industry was 59 percent higher than that of 1976. 去年工业产值比 1976 年增长了 59 ％。
My command of English is not half so good as yours. 我英语掌握得还不及你的一半儿好。
三、用 again （一倍），double （两倍），triple （三倍），fourfold （四倍）等词表示倍数。例如：
My Aunt is as old again as I am. 我姑姑的年龄比我大一倍。
The top-brand clothes are often sold as double the normal price here. 这里名牌衣服的售价经常比正常的售价高一倍。
The new work procedure tripled the output. 新工艺使产量增加两倍。
The output of grain increased fourfold. 粮食产量增加了三倍。
［巩固练习］
1. Americans eat ________ vegetables per person today as they did in 1910.
    A. more than twice      B. as twice as many  
    C. twice as many as     D. more than twice as many

2. Paper produced every year is _______ the world's production of vehicles.
    A. the three weight of         B. three times the weight of  
    C. as three times heavy as     D. three times as heavier as

3.With the help of the German experts， the factory produced ______ cars in 1993 as the year before.
    A. as twice many     B. as many twice  
    C. twice as many     D. twice many as

4. This ship measures ________ that one.
    A. as twice as long    B. as twice long as  
    C. twice long as       D. twice as long as  

5. After the new technique was introduced， the factory produced _______ tractors in 1988 as the year before.
    A. as twice many   B. as many as  
    C. as twice as many   D. twice as many

Key： 1－5 DBCDD