Unit2语法讲解及习题：基数词（Cardinal numbers）与序数词（Ordinal numbers） -2025-2026学年沪教版英语八年级上册

沪教（牛津）英语八上Unit2语法讲解及习题 基数词（Cardinal numbers）与序数词（Ordinal numbers） 一、核心语法点 1. 基本定义 基数词：表示人或事物数量多少的数词，回答 How many…? 序数词：表示人或事物的顺序、排名、第几的数词，回答 Which…? 2. 基数词 vs 序数词 对比表 类别 功能 核心规则 口诀 例句 基数词 表数量、计数 1–12 独立单词 13–19 以 -teen 结尾 20–90 整十以 -ty 结尾 21–99 十位个位加连字符 100+：百位十位加 and；具体数字不加 -s，概数加 -s 和 of 一到十二逐个记 十三到十九 -teen 尾 二十到九十 -ty 替 百位十位 and 来连 具体数字不加 s，概数才用 s 和 of The Nile River is 6,671 km long. 尼罗河长6671千米。 There are two thousand students. 有两千名学生。 序数词 表顺序、排名 1st, 2nd, 3rd 特殊 4th–19th 加 -th 整十 ty 变 tie 加 -th 几十几：前基后序 123 特殊记，末尾字母 t d d 8 去 t，9 去 e，ve 要用 f 替 整十 ty 变 tie，后面再加 -th 几十几，前基后序别忘记 Mt. Qomolangma is the first highest mountain. 珠穆朗玛峰是第一高峰。 He lives on the 21st floor. 他住在21楼。 3. 详细规则讲解 （1）基数词 1–12：one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve 13–19：thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen 20–90 整十：twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety 21–99：十位与个位加连字符，如 twenty-one 100 及以上：百位与十位加 and；具体数字前不加 -s；概数用复数 + of 例句：The world's population is over eight billion. 世界人口超过80亿。There are hundreds of amazing number patterns in nature. 自然界中有成百上千种奇妙的数字规律。 （2）序数词 1、2、3 特殊记：first, second, third 4–19 加 -th：8 去 t → eighth；9 去 e → ninth；5/12 的 ve 变 f → fifth, twelfth 整十：ty 变 tie 加 -th，如 twenty → twentieth 几十几：前基后序，如 twenty-one → twenty-first 用法： 一般情况序数词前加 the。例：January is the first month of the year. 一月是一年中的第一个月。 前面有物主代词（my, his, her 等），不加 the。例：This is my first time to visit the museum. 这是我第一次参观这个博物馆。 表示“又一、再一”，用 a/an + 序数词。例：Can I have a second cake? 我能再吃一块蛋糕吗？ 表示比赛名次，不加 the。例：He is first in the race. 他在比赛中得了第一名。 例句：January is the first month of the year. 一月是一年中的第一个月。The Yangtze River is the third longest river in the world. 长江是世界第三长河。 4. 基数词 & 序数词总表（1～90） 基数词 序数词 变化说明 1 one first (1st) 特殊变化 2 two second (2nd) 特殊变化 3 three third (3rd) 特殊变化 4 four fourth (4th) 直接加 -th 5 five fifth (5th) ve → f 加 -th 6 six sixth (6th) 直接加 -th 7 seven seventh (7th) 直接加 -th 8 eight eighth (8th) 去 t 加 -th 9 nine ninth (9th) 去 e 加 -th 10 ten tenth (10th) 直接加 -th 11 eleven eleventh (11th) 直接加 -th 12 twelve twelfth (12th) ve → f 加 -th 13 thirteen thirteenth (13th) 直接加 -th 14 fourteen fourteenth (14th) 直接加 -th 15 fifteen fifteenth (15th) 直接加 -th 16 sixteen sixteenth (16th) 直接加 -th 17 seventeen seventeenth (17th) 直接加 -th 18 eighteen eighteenth (18th) 直接加 -th 19 nineteen nineteenth (19th) 直接加 -th 20 twenty twentieth (20th) ty → tie 加 -th 21 twenty-one twenty-first (21st) 前基后序 30 thirty thirtieth (30th) ty → tie 加 -th 40 forty fortieth (40th) ty → tie 加 -th 50 fifty fiftieth (50th) ty → tie 加 -th 60 sixty sixtieth (60th) ty → tie 加 -th 70 seventy seventieth (70th) ty → tie 加 -th 80 eighty eightieth (80th) 去 t + tie 加 -th 90 ninety ninetieth (90th) ty → tie 加 -th 二、语法习题 题型一：单项选择 1. The Amazon River is about ___________ kilometres long. A. six thousand four hundred and eighty B. six thousands four hundred and eighty C. six thousand four hundreds and eighty D. six thousand four hundred eighty 2. Mt. Qomolangma is ___________ highest mountain in the world. A. one B. the first C. once D. first 3. There are ___________ students in our school. A. two thousand B. two thousands C. two thousand of D. two thousands of 4. My birthday is on the ___________ of May. A. twelve B. twelfth C. twelveth D. twenty 5. ___________ of people came to the exhibition about numbers. A. Hundred B. Hundreds C. Two hundred D. Two hundreds 6. He is ___________ person to finish the race. A. three B. the third C. thirty D. thirteen 7. The Yangtze River is ___________ longest river in the world. A. three B. the third C. thirty D. thirteen 8. There are ___________ months in a year. December is ___________ month. A. twelve; twelve B. twelfth; twelfth C. twelve; the twelfth D. twelfth; twelve 9. The number 4,189 is read as ___________. A. four thousand one hundred and eighty-nine B. four thousand and one hundred eighty-nine C. four thousands one hundred and eighty-nine D. four thousand one hundred eighty-nine 10. This is ___________ time visiting the Fibonacci exhibition. A. my second B. my two C. the second D. my two 11. Mt. Kilimanjaro is ___________ highest mountain in Africa. A. one B. the first C. once D. first 12. There are ___________ books on the shelf. I want ___________ one from the left. A. twenty; five B. twentieth; the fifth C. twenty; the fifth D. twentieth; five 13. The population of this city is over ___________. A. one million B. one millions C. million D. millions 14. He was born in the year ___________. A. nineteen ninety-five B. nineteen ninety-fifth C. nineteenth ninety-five D. nineteenth ninety-fifth 15. The ___________ lesson is about the history of numbers. A. five B. fifth C. fifty D. fifteen 题型二：用括号内单词的适当形式填空 1. The old man is ___________ (ninety) years old. Today is his ___________ (ninety) birthday. 2. There are ___________ (thousand) of people living in this city. 3. Please turn to the ___________ (twenty) page. 4. The ___________ (three) boy in the line is my brother. 5. Our classroom is on the ___________ (two) floor. 6. The number 1,000,000 is one ___________ (million). 7. There are ___________ (hundred) of stars in the sky. 8. This is the ___________ (one) time I have seen such an amazing number pattern. 9. December is the ___________ (twelve) month of the year. 10. The river is ___________ (6,300) kilometres long. 题型三：句型转换 1. The Nile River is 6,671 km long.（对划线部分提问） ___________ ___________ is the Nile River? 2. Mt. Denali is the highest mountain in North America.（改为同义句） Mt. Denali is ___________ than ___________ other mountain in North America. 3. There are three hundred and seventy-five students in Grade 8.（改为一般疑问句） ___________ there three hundred and seventy-five students in Grade 8? 4. I live on the fifth floor .（对划线部分提问） ___________ ___________ do you live on? 5. The Amazon River is longer than the Yangtze River.（改为最高级） The Amazon River is ___________ ___________ of the three rivers. 题型四：根据中文提示完成句子 1. 珠穆朗玛峰是亚洲第一高峰。 Mt. Qomolangma is the ___________ ___________ mountain in Asia. 2. 我们学校有两千名学生。 There are ___________ ___________ students in our school. 3. 他是第三个到达终点的人。 He was the ___________ person to ___________ the finishing line. 4. 成百上千的人参加了这个关于数字的讲座。 ___________ of people attended the lecture about numbers. 5. 我的生日在10月21日。 My birthday is on the ___________ of October. 三、答案与详细解析 题型一：单项选择 1. A 解析：hundred / thousand / million 前有具体数字时，不加 s。 2. B 解析：序数词前一般加 the，表示“第几”。 3. A 解析：thousand 前有具体数字时不加 s，后面不加 of。 4. B 解析：表示日期用序数词 twelfth。 5. B 解析：hundreds of 表示“成百上千的”，为固定搭配。 6. B 解析：表示顺序用 the third。 7. B 解析：表示“第三长河”用 the third longest。 8. C 解析：第一空用基数词 twelve 表数量；第二空用序数词 the twelfth 表顺序。 9. A 解析：百位和十位之间加 and，thousand 前有数字不加 s。 10. A 解析：序数词前有物主代词 my 时，不加 the。 11. B 解析：the first highest 表示“第一高峰”。 12. C 解析：第一空用基数词 twenty 表数量；第二空用 the fifth 表顺序。 13. A 解析：million 前有具体数字 one 时不加 s。 14. A 解析：年份用基数词表达。 15. B 解析：the fifth lesson 表示“第五课”。 题型二：填空 1. ninety; ninetieth 解析：第一空用基数词表年龄；第二空用序数词表“第九十个生日”。 2. thousands 解析：thousands of 固定搭配，意为“成千上万的”。 3. twentieth 解析：the twentieth page 第20页。 4. third 解析：the third boy 第三个男孩。 5. second 解析：on the second floor 在二楼。 6. million 解析：one million 一百万，前有数字不加 s。 7. hundreds 解析：hundreds of 成百上千的。 8. first 解析：the first time 第一次。 9. twelfth 解析：the twelfth month 第十二个月。 10. six thousand three hundred 解析：千位和百位之间无连字符，前有数字不加 s。 题型三：句型转换 1. How long 解析：对长度提问用 How long。 2. higher; any 解析：最高级 = 比较级 + than any other + 单数名词。 3. Are 解析：there be 句型一般疑问句，把 be 动词提前。 4. Which floor 解析：对“哪一层”提问用 Which floor。 5. the longest 解析：三者及以上比较用最高级 the longest。 题型四：完成句子 1. first highest 2. two thousand 3. third; reach 4. Hundreds 5. twenty-first ( 1 ) 学科网（北京）股份有限公司 $