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【英语】2018届二轮复习:数词学案(8页)
2018届二轮复习数词 一. 数词的基本用法 1. 基数词 100以下的基本基数词 100以上的基本基数词 1~10 11~19 20~90 1 one 2 two 3 three 4 four 5 five 6 six 7 seven 11 eleven 12 twelve 13 thirteen 14 fourteen 15 fifteen 16 sixteen 17 seventeen 18 20 twenty 30 thirty 40 forty 50 fifty 60 sixty 70 seventy 80 eighty 90 100 a / one hunderd 1,000 a / one thousand 1,000,000 a / one million 1,000,000,000 a / one billion (美) a / one thousand million (英) 8 eight 9 nine 10 ten eighteen 19 nineteen ninety 1~12为独立单词 13~19在个位数词的词干上加后缀-teen构成 20~90以-ty结尾 21~99在十位与个位之间加连字符“-”,如36写成thirty-six 101~999由hundred加and再加二位数或末位数,如263写成two hunderd and sixty-three 506写成five hunderd and six hundred,thousand,million以及billion表示确切数字时不能加-s,如five hunderd;而在表示不确定数目时,表示“数以……计的”,要用复数形式,如hundreds of;thousand of;millions of。 温馨提示: 英语中没有表示“万”和“亿”的数词,“万”用“十千”即“ten thousand”表示;“亿”则用“100个百万”即“one hundred million”表示。 书写四位以上的数字时,右起每三位加一个“,”。每一个“,”号的前一位依次为thousand,million,billion。如123,406,571,982,读作“one hundred and twenty-three billion four hundred and six million five hundred and seventy-one thousand nine hundred and eight-two”. dozen的用法 A. 与数词,many,several等连用时,不加“-s”,所修饰的名词前常省去“of”。 如two dozen eggs many dozen pencils B. 当所修饰的名词之前有限定词these,those,my,your等或是人称代词宾格them,us,you时,这时需要加of。如two dozen of these pens three dozen of them C. dozen用其复数形式,后加of表示不的数量,意为“许多,几十”。如dozens of people score的用法 A. 单复数形式相同,与基数词连用共同修饰名词时,除a score of外,其他情况下不加of。 如two score eggs three score people four score and ten pigs B. 其复数形式后加of,表示不确定数量,意为“许多”,如scores of students 2. 序数词 从第一至第十九 其中,one—first, two—second, three—third, five—fifth, eight—eighth, nine—ninth, twelve—twelfth为特殊形式,其他的序数词都是由其相对应的基数词后面添加“th”构成。如six—sixth 从二十至第九十九 整数第几十的形成由其对应的基数词改变词尾字母y为i,再加“eth”构成。 如twenty—twentieth。表示第几十几时,用几十的基数词形式加上连字符“-”和个位序数词形式一起表示。如第三十一 thirty—first 第一百以上的多位序数词 由基数词的形式变最后数为序数词形式来表达。 如第一百二十一 one hundred and twenty-first 序数词的缩写形式 温馨提示: 序数词前面通常加定冠词the,表示“第几”,但也可以在前面用不定冠词a或an,意为“又……再……。如Try a secone time and you’ll succeed. After having the fourth apple, the boy ate a fifth one. 基数词与序数词连用时,通常是序数词在前。如the first three pages of the book 序数词之前已有物主代词、指示代词或名词所有格修饰时,不用定冠词。 如I’ll never forget that first lesson taught by Mr Wang. Have you read his second novel? 二. 小数、分数、百分数的表达法及基本用法 1. 分数由基数词和序数词合成,分子用基数词,分母用序数词。分子大于1时,分母的序数词要用复数形式。如三分之一one (a) third 三分之二 two thirds 一又三分之二one and two thirds 注意:二分之一one (a) half 四分之一one (a) quarter 2. 百分数由基数词后直接加percent构成。如30% 30 percent (per cent) 3. 表示几分之几(或百分之几)的人或物时,须在分数(或百分数)和人或物间加of。若充当主语,谓语动词的数须和of后的名词的数保持一致。 如About three-fifths of the workers in that steel works are young people. Sixty percent of her income was spent on clothes. 温馨提示:分数、百分数等也可用于下面的各种表达法中。如We increased 20% as many products as last year. We lost the game by one score. 三. 倍数的表达法 表示倍数时,一倍用once,两倍用twice / double,三倍以上用基数词 + times。数词表达倍数主要有以下几种方式: 1. double / twice / three times / four times as many / much…as…型 如We have produced three times as many computers as we did last year. 2. double / twice / three times / four times the size of…型 用法与size相同的名词常用的有:weight, height, depth, width, age, length等。如China is almost twice / double the size of Mexico in area. 3. double / twice / three times / four times + what从句型 如The length of the road is twice / double what is was three years ago. 4. double / twice / three times / four times + 比较级 + than型 如I am twice older than you. He has read three times more books than I have. 5. 比较级 + than …+ by + 倍数程度型 如The line is longer than that one by twice. 四. 数学公式中的加、减、乘、除表达法 加法用plus,减法用minus,乘法用times,除法用divided by表示;等号用is或equals或is equal to表示。如Nine and thirty is thirty-nine.=Nine plus thirty is thirty-nine Ten minus three is seven. = Three from ten leaves seven. Seven times seven equals forty-nine. Thirty-six divided by six is six. 五. 编号表达法 基数词,序数词均可用于编号,习惯上多用基数词,尤其是数字较长时。 如Number 3 Middle School Class Six, Grade Two Room 405 (four 0 five) 0543-3323086 (0 five four three- three three two three 0 eight six 六. 时间的表达法 1. 年月日的表达法 英语中年月日的表达法与中文不一样,它可以有两种形式,即:月、日、年或日、月、年。年份要放在最后,且多用阿拉伯数字表示;月份只能用英语表示;日期通常用序数词读出。如1999年2月28日 Feb 28th,1999 2. 钟点表达法 6点 at 6:00 / at six o’clock / at 6 o’clock / at six 6点15分 at 6:15 / at fifteen past six / at six fifteen 6点40分 at 6:40 / at twenty to seven / at six forty 注意:当分钟>30时,一般用介词to 如8:45 at fifteen to nine 当分钟≤30时,一般用介词past 如8:15 at fifteen past eight 3. 年龄表示法 用基数词表示年龄。如The boy is ten (years old). 表示在多大年龄时,其前用介词at,即at(+ the age of)+ 基数词。 如at the age of 17 = at 17 表示“在某人的几十岁”时,可用介词in + one’s + 整十位数的复数形式。 如Tom worked as a doctor in his thirties 与基数词合成的定语,其中的名词用单数。如a five-year-old boy; a ten-year plan 表示“一个五岁的男孩”,如a boy of five = a boy of five years old = a boy of five years of age = a five-year-old boy 七. 数词的语法功能 数词在句子中,可以充当主语、宾语、表语、定语、状语、同位语。 如The third is better than the other two.(主语) Sunday is the first day of a week.(定语) Is there any food left for us two?(同位语) This rope is one-fifth longer than one.(状语) Mr. Smith was the tenth to be present.(表语) I prefer the second to the first.(宾语)查看更多