资源简介

数词讲义
一、定义
数词分基数词和序数词。基数词表示数目,序数词表示顺序。简单的说基数词就是数字几几几，那么序数词就是第几第几第几。序数词由基数词变化而成。
二、数词的用法
1、表示编号：可在数字（用基数词表示）前加number，简写为No.。如：Bus No.65
2、表示倍数：
①倍数+as+形容词/副词（原级）+as。
如：The classroom is twice as big as that one. 这间教室是那间教室的两倍大。
②倍数+形容词或副词的比较级+than。
如：This lion is four times bigger than that one. 这头狮子是那头狮子的四倍大。
③倍数+thesize/length/weight/width/height…+of+表示比较对象的名词。
如：This river is six times the depth of that one. 这条河是那条河的六倍深。
④倍数+what引导的从句。
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。
3、表示约数：
①用“dozens/scores/hundreds/thousands/millions+of”表示“几十、几百、上千、成千上万”等。
如：Thousands of people died in the earthquake. 数以千计的人死于地震。
②用more than, beyond, or more, over, above等来表示超过或多于某个数目。用less than, under, below, almost, nearly, upto等来表示小于或接近某数目。
如：nearly two hours 近两个小时 more than 100 years 一百多年 under thirty years of age 小于三十岁。
③用about, around, some等表示在某一数目左右。
如：about 50 pens 大约五十支钢笔。
4、表示分数：
①遇到分数时，分数的分子用基数词表示，分母用序数词表示（当分子大于一时，分母的序数词要用复数）。
②分子与分母之间加in，分子在前，分母在后，分子分母都用基数词。
如：one in ten 十分之一，five in eight 八分之五。
③分子与分母之间加out of，分子在前，分母在后，分子分母都用基数词。
如：five out of seven 七分之五 three out of ten 十分之三。
5、表示百分数：在表达百分数时，用“基数词（或者小数）+percent（%）” percent用单数形式。
6、表示小数：小数点前的数按基数词的读法读，小数点以后的数按一个一个的数字读，小数点用point。
三、基数词的用法：
1、基数词在句中主要用作主语、宾语、定语、表陆帆语、同位语。
2、表示一个具体数字时，hundred, thousand, million一律不用复数；在表示一个不确定数字时则用复数。
3、表示“……十”的数词的复数形式可用来表示人的岁数或年代。
4、表示时刻用基数词。
如：We get up at six. The workers begin work at eight. 表示“几点过几分”，用介词past，但须在半小时以内。
如：ten past ten, a quarter past nine, half past twelve 表示“几点差几分”用介词to，但分数须在半小时以上。
如：twenty to nine, five to eight, a quarter to ten 表示“几点几分”还可直接用基数词。
如：seven fifteen, eleven thirty, nine twenty。
四、序数词的用法：
1、序数词主要用作定语，前面要加定冠词。
2、序数词有时前面可加不定冠词来表示“再一”，“又一”这样的意思。
3、由几个序数词和基数词在拼写时不对应，很容易写错，应特别注意。它们是：one—first, two—second, three—third, five—fifth, eight—eighth, nine—ninth, twelve—twelfth。
4、表示年，月，日时，年用基数词表示，日用序数词表示。
5、表示分数时，分子用基数词表示，分母用序数词表示。分子大于1时，分母加-s。
6、序数词有时用缩写形式：first→1st, second→2nd, third→3rd, fourth→4th, twenty-second→22nd。
五、数词表示法图标示例
1-10 11-19 20-90 100-10亿
one two three four Five six seven eight nine ten Eleven Twelve Thirteen Fourteen Fifteen Sixteen Seventeen Eighteen nineteen Twenty Thirty Forty fifty Sixty Seventy Eighty ninety hundred (百) thousand (千) million (百万) billion (十亿)
拓展：
①当hundred, thousand, million, billion等和of连用，表示粗略的数目时,须用复数。
如hundreds of people数以百计的人;
但如果hundred, thousand, million, billion等词前有具体数词或several时，须用单数six hundred people 600人.
②表示“几十年代”或“几十岁”时，用逢十的基数词的复数。
如：in the thirties在30年代 in his fifties在他50多岁时
③与基数词合成的复合形容词，其中的名词用单数。
如：a three-month-old baby三个月大的婴儿 a five-year plan一个五年计划
用法速记口诀： 有无无，无有有
注释：
有无无：当hundred,thousand,million前有确切数字时，其后无s无of;
无有有：当hundred,thousand,million 前无确切数字时，其后有s有of,表示“成······上······”。
④2. 20以上的两位数的读写：十位数加个位数，中间加连字符“-”，即“C-A”。
21：twenty-one 56：fifty-six
⑤三位数的读写：百位数（1~9）+hundred + and +后两位或一位数。
101：one hundred and one
218：two hundred and eighteen
⑥四位数及四位数以上的读写：从后往前数，每三位数为一段，用逗号分开，分别使用的单位为thousand, million, billion. 读的时候从前往后读，即：多少个billion→多少个million→多少个thousand→后三位或两位或一位数。
1,321：one thousand three hundred and twenty-one
六、序数词的细化分析
表示顺序的先后。如：first (第一),second (第二)，third (第三)…
1.基数词变序数词的特殊变化：
one----first two----second three----third five----fifth
eight----eighth nine----ninth twelve----twelfth
2.一般在基数词后面加th, 构成序数词：
four----fourth six----sixth seven----seventh ten----tenth
eleven----eleventh thirteen----thirteenth fourteen----fourteenth
3.十位数的基数词，改y为i, 再加eth ：
twenty----twentieth thirty----thirtieth forty----fortieth
4.20以上的基数词变成序数词，只把后一位或两位数变成序数词：
twenty-one----twenty-first forty-three----forty-third
one hundred and two----one hundred and second
5.序数词的缩写形式：阿拉伯数字+后两个字母：
first----1st second----2nd third----3rd fourth----4th
twelfth----12th twenty-fifth----25th one hundred and first----101st
七、练习题
1．—John gave away __________ new books to the poor children in the small village.
—Wow, how kind he is!
A．hundred of B．hundreds of C．two hundreds
2．My sister is ________ now. She had a party for her ________ birthday yesterday.
A．twenty; twentieth B．twenty; twenty C．twentieth; twenty
3．My classmate Vince likes collecting CDs. He has ________ them.
A．hundred of B．hundreds of C．many hundreds of
4．—We planted ________ trees in one day.
—How great you were!
A．Hundreds B．hundred C．hundreds of D．hundred of
5．About ________ students in our school attended the concert in Shanghai Concert Hall.
A．three hundred of B．three hundreds
C．three hundred D．hundred of
6.（22-23八年级上·广东广州·期中）Please turn to Page 40 and look at the ________ picture in Lesson ________.
A．five；First B．fifth；First C．fifth；One D．five；One
7.（22-23八年级上·广东广州·期中）It is said that COVID-19 has killed more than ________ people around the world.
A．6 millions B．6 millions’ C．6 millions of D．6 million
8.（21-22八年级上·广东江门·期中）They are old because they were born ________.
A．in the 1950 B．at the 1950s C．in the 1950s D．at the 1950
9.（21-22八年级上·广东广州·期中）There are ________ storeys（层）in this building and I live on the ________ floor.
A．twenty-five; eighteenth B．twenty-five; eighteen
C．Twenty-fifth; eighteen D．twenty-fifth; eighteenth
10.（22-23八年级上·广东江门·期中）________ people come to visit the Great Wall every year.
A．Six millions B．Million of C．Millions of D．Six millions of
11.（23-24九年级上·广东深圳·开学考试）In our class, _______ of the students _______ girls.
A．three fifth; are B．three fifth; is
C．three fifths; are D．three fifths; is
12.（21-22八年级上·广东深圳·期末）________ of the land ________ covered with trees in our city.
A．Two fifth; is B．Two fifth; are C．Two fifths; is D．Two fifths; are
13.（21-22八年级上·广东深圳·期末）I went to Mr. Wang’s ________ birthday party. He looks young although he is in his________.
A．eighty’s; eighty B．eighty; eighties
C．eightieth; eighties D．eightieth; eighty
14.（21-22八年级上·广东广州·期末）It’s my ________ time to visit the Canton Tower. It’s a wonderful experience for me.
A．one B．the one C．first D．the first
15.（22-23八年级上·广东广州·单元测试）—Dad, about ________ of our classmates wear glasses.
—Oh, that’s terrible. You all should take care of your eyes.
A．three fourth B．third fourth C．third fourths D．three quarters
写出下列序数词的缩写形式
(1) first ________ (2) second ________ (3) third ________
(4) fourth ________ (5) fifth ________ (6) twenty-first ________
(7) thirty-second ________ (8) forty-third ________ (9) fifty-fourth ________
(10) sixty-fifth ________
写出下列基数词和序数词
(1) 1 ________ ________ (2) 2 ________ ________
(3) 3 ________ ________ (4) 4 ________ ________
(5) 5 ________ ________ (6) 6 ________ ________
(7) 7 ________ ________ (8) 8 ________ ________
(9) 9 ________ ________ (10) 12 ________ ________

展开更多......

收起↑