寒假英语总动员温故篇之不可忽略的数词
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  英语中的数词包括基数词和序数词两大类,它们的用法非常复杂,为了便于同学们系统地复习数词,现就初中阶段数词的主要内容作以下归纳。

  一、基本构成

  (一)基数词——从1数到N

  1.1—12的基数词是独立的单词,即: one,two,three,four,five,six,seven,eight, nine,ten,eleven,twelve。

  2.13—19的基数词以-teen结尾。如: fourteen,seventeen等,但13,15,18较特殊, 13—thirteen 15—fifteen 18—eighteen。

  3.20—90的整十位均以-ty结尾。如: sixty,ninety,但20,30,40,50,80较特殊, 20—twenty, 30—thirty, 40—forty ,50—fifty ,80—eighty。

  4.十位数与个位数之间要加连字符号“-”,如:28—twenty-eight,96—ninety-six。

  5.百位和十位(若无十位则和个位)之间加and,如:148—one hundred and forty-eight ,406—four hundred and six。

  6.hundred(百),thousand(千),million(百万),billion(十亿)等前面即使有具体的数词,也不能在它们的后面加s。如:600—six hundred,8百万—eight million。

  7.1000以上的数字,从后往前数每三位加一个逗号“,”第一个逗号前为千(thousand),第二个逗号前为百万(million),第三个逗号前为billion(十亿)。英语中无“万”这个词,我们可以用“几十个千(thousand)”表示几万,“几百个千(thousand)”表示“几十万”。如:2,510=two thousand five hundred and ten;84,296=eighty-four thousand two hundred and ninety-six;274,350=two hundred and seventy-four thousand three hundred and fifty。

  8.hundred,thousand,million用复数形式修饰名词时要用“of+复数名词”,如:数以百计的年轻人hundreds of young people;数以千计的书thousands of books。注意:hundreds of /thousands of/millions of +复数名词,其前面不能加具体的数词,但可加several或 many。

  Hundreds of new buildings have sprung up here this year.

  Thousands upon thousands of people in South Africa are rising against their oppressors.

  Thousands and thousands of people come to visit the city every day.

  Millions of dollars have gone into the building of this factory.

  (二)序数词——由基数词转变而来,表示“这是第N个”

  1.口诀巧记基数词变序数词:“一、二、三,特殊记,八去“t”,九去“e”,“ve”要用“f”替,见“y”变成“i”和“e”,词尾加上“th”,若是遇到几十几,只变个位就可以。”第一、第二、第三分别:first,second,third,eight—eighth nine—ninth,five—fifth,twelve—twelfth,twenty—twentieth,forty—fortieth,twenty-five—twenty-fifth。

  2其余情况均在基数词后加th。如: six—sixth, nineteen—nineteenth , hundred— hundredth, thousand—thousandth等。

  3.序数词有时用缩写形式:

  first----1st, twenty—second-------22th.

    二、基本用法

  (一)基数词的基本用法

  1.定语

  Fifty thousand London dockers are out on strike.

  2.主语

  数词作主语,谓语动词用单数。

  如: Two months is quite a long time.

  Five is an odd number.

  3.宾语或介词宾语

  How many do you want? -----Eight, please.

  The city has a population of four million.

  4.表语

  We are altogether fourteen.

  Five plus seven is twelve.

  5.同位语

  What work are you to assign us three?

  Is there room for us two?

  6.基数词+单数名词+形容词构成合成形容词。如:一个五岁的男孩a five-year-old boy;一座800米长的桥an 800-metre-long bridge;女子400米接力girls'400-metre relay1 race。

  7.句型:主语+is +about(大约)/ over =more than(超过)/nearly(接近)+具体数词+metre(s)/kilometre(s)/kilo(s)long / high /tall /deep /away等。如:长江长6300公里。

  The Changjiang River is 6,300 kilometres long.

  8.表示“。。。。。。十”的数词的复数形式可以用来表示人的岁数或年代:

  He is in his early thirties.

  He died still in his forties.

  This took place in the 1930s.

  (二)序数词的基本用法

  1.序数词主要用作定语,前面一般要加定冠词(或物主代词):

  Tom is their second son.

  They celebrated2 the 10th anniversary of the founding of the republic.

  I will never give up, not even on the 1,000th or 10,000th try.

  2.有时前面可以加一个不定冠词来表示“再一”, “又一”这样的意思:

  We’ll have to do it a second time.

  Shall I ask him a third time?

  When I sat down, a fourth man rose to speak.

  3.First,second 等有时可用来表示“第一个人(批)”“第二个人”等:

  She was among the first to come and settle in Dujiashan.

  You will be the second to speak.

  4.如果数字较长,序数词总避免使用,而且读的方法也常常简化:

  第201房间: Room 201

  第319面: page 319

  第一拖拉机厂:the Number I Tractor Works

  第六号车厢:Carriage No.6

  南京路1490号:1490 Nanjing Road

  电话号码55――2347:telephone number : 55—2347

  5. 在谈编了号的东西时,我们可以用基数词表示顺序:

  the first part------part one

  the third squad------squad three

  the twenty-third section----section twenty-three
  三、特殊数字的表示法

  (一)年 月 日表示法

  1. 年代 年代前用 in.

  ( in ) 897 读作 ( in ) eight hundred and ninety-seven

  ( in ) 1961 读作 ( in ) nineteen sixty-one (或 in nineteen hundred and sixty-one)

  ( in ) 1905 读作(in ) nineteen and five

  ( in ) 1800 读作( in ) eighteen hundred

  2. 月份 月份开头第一个字母须大写,表示“在某月”时, 月份前面用 in。下面月份后附有缩写式。

  ( in ) January Jan. ( in ) March Mar3. ( in ) December Dec.

  3. 日期 用序数词(前需要加the)表示; “ 在某日”, 前面用介词on.

  ( on ) the first ( on ) the eighteenth ( on ) the thirty-second

  4. 某年 某月 某日

  in Sep. 1954 on May 17, 1960 on Oct. 1, 1949(读作on October the first, nineteen forty-nine)

  注:当年月日完全用数字表示时, 美国人把月放在日前。 8,6,79在英国表示June the eighth (79年6月8日), 但是在美国却表示August the sixth (79年8月6日)。

  (二)时刻表示法

  1.英语通常用at所引导的表示时刻。如:

  ( at ) six or six o’clock

  ( at ) eight or eight o’clock

  2.如说几点几分,用下面的方法

  a)表示几点过几分,用介词, 但分数须在半小时以内包括半小时。如:

  eleven past seven

  a quarter past eight

  half past nine

  b)表示几点差几分,用介词to, 但分数需要在半小时以上不包括半小时。 如:

  two to seven

  a quarter to eight

  eighteen to nine

  注:上午可以用am表示,下午用pm表示,例如:

  9.50am 11.05pm

  (三)分数词表示法

  1.分数词是以基数词和序数词合成的,基数词代表分子,序数词代表分母,除了分子是“1”的情况外,序数词都是用复数,(分子用基数词,分母用序数词,分子大于“1”,分母则加“s”)如:

  1/4 one-fourth 2/3 two-thirds 7/9 seven-ninths 5/12 five-twelfths

  2.另外还有下面一些表示法:

  1/2 (one) a half 1/4 a (one ) quarter 3/4 three-quarters

  (四)小数的表示法

  7.8 ------seven point eight

  0.4---------zero point four

  0.125----- zero point one two five

  603.09---six hundred and three point oh nine

  小数作定语时较多:

  Its total industrial output value was up 5.6 times in these years.

  Our grain output is now 2.4 times that of 1970.

  (五)百分数的表示法

  百分数由per cent 表示,常常和by连用,作状语也可单独作状语:

  Its total output value increased by 11.5 per cent over the previous year.

  The output of cars in the U. S. last year was 24 per cent less than in 1973.

  有时用作定语 宾语等:

  The loss of metal has been reduced to less than 20%.

  The March figure for output value registered a 37% increase over February.

  (六)倍数的表示法:

  一倍用once,两倍用 twice,两倍以上用基数词+times。如:5倍five times。

  (七)一些数学公式的读法:

  3+8=11 Three plus eight is eleven.

  9-7=2 Nine minus seven is two.

  a>b a is more than b.

  a

  (八)约数的表示法

  ⑴ “多于”用more than 或over

  This room can hold more than (=over) 500 people.这间屋子能容纳500多人。

  ⑵ “少于”用less than

  There are less than thirty balls in the basket.篮子里不到三十个球。

  ⑶ “或……以上”用or more

  The music hall can hold 7000 people or more.音乐厅能容纳7000人或7000人以上。

  ⑷ “或……以下”用or less

  The house can hold 50 people or less. 这座房子可容纳50人或50人以下。

  ⑸ “大约”用about, around, nearly等

  The box weights about 50 pounds.这个箱子重约50磅。

  ⑹ “左右”用or so

  In the past ten years or so , they have changed a lot.在过去的十年左右的时间里,他们改变了许多。

 



点击收听单词发音收听单词发音  

1 relay cV9xi     
n.接力赛,中继转播(设备);vt.转述,转播
参考例句:
  • They will relay your message.他们会转达你的口信。
  • This metal tower is used to relay television signals to distant villages.这个金属塔是用于向遥远的村子转播电视讯号的。
2 celebrated iwLzpz     
adj.有名的,声誉卓著的
参考例句:
  • He was soon one of the most celebrated young painters in England.不久他就成了英格兰最负盛名的年轻画家之一。
  • The celebrated violinist was mobbed by the audience.观众团团围住了这位著名的小提琴演奏家。
3 mar f7Kzq     
vt.破坏,毁坏,弄糟
参考例句:
  • It was not the custom for elderly people to mar the picnics with their presence.大人们照例不参加这样的野餐以免扫兴。
  • Such a marriage might mar your career.这样的婚姻说不定会毁了你的一生。
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