分数 知识点
分数的表示方法:
一、用“基数词+序数词”表示,其中基数词表示分子,序数词表示分母。
例如: However, the number of boys will one third or less than the girls in the class但是,班里男生的人数将比女生少三分之一或更少。
注意:1.分子除用one外,也可用a;如果分子大于1,分母要用复数形式。但是,1/2不能说a( one) second,而要说a (one) half。
2. 1 / 4和3/ 4可以说a( one) fourth和three fourths, 但常用a quarter和three quarters表示。 应该注意的是,分数修饰名词时,若该名词是不可数名词只能用单数;若是可数名词,用单数或复数均可。但是,若它们在句子中作主语,则谓语动词是用单数还是复数取决于名词,即与分数所修饰的名词保持一致。
例如:① Only one-fifth of airconsists ofoxygen.氧气只占空气的1/5。
② About two thirds of the students attend the meeting.大约2/ 3的学生都参加了会议。
二、 用“基数词+介词+基数词”表示,借助介词表示分数,介词前的数词是分子,介词后的数词是分母。
例如: Ninety-nine people out of a hundred if they were asked who firstfound America, would answer Clumbus. 如果要问是谁首先发现美洲,一百个人中有九十九个将回答是哥伦布。
注意:这种结构中的介词主要有in, out of, of 以及to。例如:The map is drawn to a scale of one of ten thousand.地图是按一万分之一的比例绘制的。
三、百分数的表达:常用percent表示,百分之一也可以说one( a ) hundredth,但更常用one percent或per cent即用百分数表示法来表达。
例如: Seventy-five percent of the earth' s sur face is covered by water. 地球表面的75%被水覆盖着。
四、带分数的表达。所谓带分数,实际上是“整数+分数”,表达时分而述之,只是整数部分与分数部分要用连词and连接。当带分数修饰名词时,该名词通常是复数,但若名词置于整数one或a之后,则用单数。“带分数+名词”作主语时,要用复数。
例如: You should finish the work within one and a fourth hours. 你应在1. 25小时内完成工作。
分数 知识点题库
About ________ of his spare time ________ spent in reading.
A . third-fifths; are
B . three-fifths; is
C . three-fives; are
D . three-fifth; is
About ________ of the students are from foreign countries.
A . three four
B . three fourth
C . third fourth
D . three fourths
of the money used up.
A . Three-five; are
B . Three-fifths; have been
C . Three-fifths; has been
D . Third-fifths; is
_____ of the trees in the garden are apple trees.
A . Two third
B . Two thirds
C . Second third
D . Second thirds
China's population is about _______ of the world's population.
A . the quarter
B . one-four
C . a quarter
D . one-fourths
Two of the population of the state immigrants.
A . thirds, are
B . third, is
C . thirds, is
D . third, are
______ of the buildings were ruined.
A . Three fourth
B . Three four
C . Three-fourths
D . Three-four
The moon is about _____ in diameter as diameter as the earth.
A . one-three as large
B . one three as large
C . one-third as large
D . one third as large
He did it it took the girl.
A . one-fourth a time
B . one-fourth time
C . the one-fourth time
D . one-fourth the time
of the land in that district covered with trees and grass.
A . two fifth, is
B . two fifths, is
C . two fifth, are
D . two fifths, are
Almost________ of the students in this class wear glasses, that is ________of them.
A . two thirds; 60 percent
B . two thirds; 60 percents
C . two third; 60 percent
D . two third; 60 percents
____ of the land in that country ______ covered with trees and grass.
A . Two fifth; is
B . Two fifth; are
C . Two fifths; is
D . Two fifths; are
—How many teachers are there in your school?
—Over four ________. And ________ of them are women teachers.
A . hundred; two-thirds
B . hundred; two-third
C . hundreds; two-thirds
D . hundreds; two-third
About ________ of the surface of the earth is covered with water.
A . three fourth
B . three fourths
C . third fourth
D . third fours
________of the money was donated to the injured.
A . Three fifth
B . Three five
C . Third fifths
D . Three fifths
________of the land in that district________ covered with trees and grass.
A . Two fifths; is
B . Two fifth; are
C . Two fifth; is
D . Two fifths; are
_____ of the land in that district _____ covered with trees and grasses.
A . Two-fifth; is
B . Two-fifth; are
C . Two-fifths; is
D . Two-fifths; are
Nearly two (three) of the students in our class like playing football.
The number of families seeking food supplies rose by 12(百分比).
The disease a fully 30 p of the population.