Unit 2 Amazing numbers 语法Grammar 基数词和序数词-2026-2027学年八年级英语上册单元练习（沪教版）

**基本信息** 聚焦基数词与序数词系统训练，通过分类规则梳理与梯度练习，构建数字表达的完整知识网络，提升语言应用与思维品质。 **专项设计** |模块|题量/典例|方法提炼|知识逻辑| |----|-----------|----------|----------| |基数词|7类规则（0-12至多位数）|分类记忆法（按数字范围分层）|从基础数字到多位数表达，逐步构建数字认知体系| |序数词|4类规则（1-3至多位数）|规则转换法（不规则/规则变化）|基于基数词规则延伸，强化词形转换逻辑| |综合应用|40题分层练习（填空+选择）|情境应用法（年龄/年代/数量表达）|从规则记忆到实际语境运用，提升语言能力|

班级 姓名 学号 分数 Unit 2 Amazing numbers 基数词和序数词 （时间：60分钟，满分：100分） 考点一 基数词 0-12 one two three four five six seven eight nine ten eleven twelve 13-19 thirteen fourteen fifteen sixteen seventeen eighteen nineteen 20-90 整数 twenty thirty forty fifty sixty seventy eighty ninety 20-99 非整数 twenty-one forty-two 三位数 121 one hundred and twenty-one 206 two hundred and six 多位数 1,987,654,321 one billion nine hundred and eighty-seven million six hundred and fifty-four thousand three hundred and twenty-one 不确切数 hundreds of thousands of millions of 不确切岁数/年代 in her forties in the 1990s 考点二 序数词 1 、2 、3 不规则变化 first second third 1st 2nd 3rd 4-19 基数词词尾加 th fourth fifth sixth seventh eighth ninth tenth eleventh twelfth thirteenth 4th 11th 20th 21st 22nd 23rd 24th 121st 124th 20-90 整数 ty 变为 tie 再加 th twentieth thirtieth fortieth 两位数或多位数(整数 除外)只变个位数 twenty-first one hundred and thirty-fourth 一、写出下列数字的基数词，并对比记忆写出序数词(本大题共10小题，每小题4分，共40分) 1．4 ________________, _________________ 2．10 ______________, _______________ 3．12 ___________________, ___________________ 4．15 ______________, _______________ 5．8 ______________, ________________ 6．9 _______________, _______________ 7．21_______________, ___________________ 8．72 ______________, _______________ 9．40 ________________, _________________ 10．20______________, __________________ 二、单项选择(本大题共30小题，每小题2分，共60分) 11．—Which sentence do you like best in The Little Prince? —Maybe there are five ________ roses in the world just like you, but you’re my unique rose. A．thousand B．thousands C．thousand of D．thousands of 12．Every year, ________ people come to visit the Great Wall. A．hundred B．hundreds C．hundred of D．hundreds of 13．My grandfather is ________ years old. Today is his ________ birthday. A．ninty-nine; ninety-nineth B．ninety-ninth; ninety-nine C．ninety-nine; ninetieth-nine D．ninety-nine; ninety-ninth 14．There are _________ months in a year and May is _________ month of the year. A．twelve; the fifth B．twelve; five C．twelfth; five D．twelfth; the fifth 15．—How many teachers are there in your school?   —About ________. And ________ them are women teachers. A．three hundreds, two hundred of B．three hundred, two hundred of C．three hundred, two hundreds of D．three hundreds, two hundreds of 16．In our city, the number of the teachers________ about 2,000, but only about ________ of them are men teachers. A．is;seven hundreds B．are;seven hundred C．is;seven hundred D．are;seven hundreds 17．—Neil, can you read the number 15,859? —Yes, I can. It’s ________. A．fifteen thousands eight hundred and fifty-nine B．fifteen thousand eight hundreds and fifty-nine C．fifteen thousand eight hundred and fifty-nine D．fifteen thousand and eight hundred and fifty-nine 18．________ of the money ________ used to help the poor children in mountain areas. A．Three-fourths; are B．Three-fourths; is C．Third-fourths; are D．Three-fourth; is 19．—Have you heard of the famous writer? —Certainly. About ________ teenagers love him very much in our school. A．hundreds B．two hundreds of C．two hundreds D．two hundred 20．There are ________ days in a year. A．three hundreds and sixty five B．three hundred and sixty five C．three hundred and sixty-five D．three hundred sixty-five 21．—Can you teach me how to read the number 65,023 in English, Peter? —Yes. It’s ________. A．sixty-five thousands and twenty-three B．sixty-five thousands, twenty-three C．sixty-five thousand, twenty-three D．sixty-five thousand and twenty-three 22．There are ________ teachers in No. 1 Middle School. ________ of them are women teachers. A．hundreds; Two hundreds B．hundreds of; Two hundreds C．hundreds of; Two hundred 23．Which number is six hundred and seventy-three thousand one hundred and eleven? A．6,073,100 B．60,731,100 C．6,731,11 D．673,111 24．How do you say 3,456? A．Three thousands four hundred and fifty-six. B．Three thousand four hundred and fifty-six. C．Three thousand four hundred fifty-six. D．Three thousands four hundred fifty-six. 25．—Look at the picture! There were so many people watching Suchao last night. — ________? That’s so amazing. A．Sixty-one thousand, one hundred and six B．Sixty-one thousand, one hundred zero six C．Sixty-one thousands, one hundred and six D．Sixty-one thousands, one hundred zero six 26．— Do you know how to read the big number “815,096”, David? — Yes! It’s________. A．eight hundred fifty-one thousand and ninety-six B．eighty-one thousand five hundred and ninety-six C．eight hundred and fifteen thousand and ninety-six D．eight million one hundred five thousand and ninety-six 27．My cousin will be ________ years old next month, and we plan to celebrate his ________ birthday at a fancy restaurant. A．twelve; twelve B．twelfth; twelve C．twelve; twelfth D．twelfth; twelfth 28．—Simon, how old is your grandpa this year? —________. And we are planning a special birthday party for his ________ birthday this Sunday. A．Ninetieth; ninety B．Ninety; the ninetieth C．Ninety; ninetieth D．Ninetieth; the ninety 29．—Do you know how to read the number 5,050,179?   —Yes, I can. It is ________. A．Five millions, fifty thousands, one hundred and seventy-nine. B．Five millions, fifty thousands, one hundred seventy-nine. C．Five million, fifty thousand, one hundred seventy-nine. D．Five million, fifty thousand, one hundred and seventy-nine. 30．We planted ________ trees last year. Three ________ of them are in the park. A．thousands of; hundred B．thousand of; hundred C．thousands of; hundreds D．thousand of; hundreds 31．—It is Mum’s ________ birthday next Wednesday. What should we do? —How about buying her ________ flowers to show our love? A．forty; forty B．fortieth; forty C．forty; fortieth D．fortieth; fortieth 32．Please turn to Page ________ and look at the ________ picture from the left. A．Ten; three B．Tenth; third C．Ten; third D．Tenth; three 33．We read 23,813 like this: ________. A．twenty-three thousands, eight hundred and thirteen B．twenty-three thousands and eight hundred and thirteen C．twenty-three thousand, eight hundred and thirteen D．twenty-three thousand, eight hundred thirteen 34．There are ________ students in our school. Five hundred of them are boys. A．nine hundred B．nine hundreds C．nine hundred of D．nine hundreds of 35．There are about __________ elephants in this zoo. A．twelfth B．twentieth C．twenty D．twenties 36．—Excuse me, can you read the number “________” in English? —Of course. Eight million, three hundred and sixty-three thousand. A．8,360,360 B．8,660,360 C．8,363,000 37．— Excuse me, can you tell me how to say 5,510,628 in English? — Sure. It’s ________ A．five million, five hundred ten thousand, six hundred twenty-eight B．five billion, five hundred and ten million, six hundred and twenty eight. C．five million, five hundred and ten thousand, six hundred and twenty-eight. 38．Jim will turn _________ tomorrow and there will be a party for his _________ birthday. A．twenty; twenty B．twentieth; twentieth C．twenty; twentieth D．twentieth; twenty 39．Please turn to Page ________, boys and girls. Today, we are going to learn ________ unit. A．Fifth; Five B．Five; the five C．Fifth; the fifth D．Five; the fifth 40．—If a=10, b=3, what’s the answer to the question “ab+3”?    —________. A．Sixty B．Seventy-three C．Thirty-three D．Thirty 试卷第1页，共3页 试卷第1页，共3页 学科网（北京）股份有限公司 $ 班级 姓名 学号 分数 Unit 2 Amazing numbers 基数词和序数词 （时间：60分钟，满分：100分） 考点一 基数词 0-12 one two three four five six seven eight nine ten eleven twelve 13-19 thirteen fourteen fifteen sixteen seventeen eighteen nineteen 20-90 整数 twenty thirty forty fifty sixty seventy eighty ninety 20-99 非整数 twenty-one forty-two 三位数 121 one hundred and twenty-one 206 two hundred and six 多位数 1,987,654,321 one billion nine hundred and eighty-seven million six hundred and fifty-four thousand three hundred and twenty-one 不确切数 hundreds of thousands of millions of 不确切岁数/年代 in her forties in the 1990s 考点二 序数词 1 、2 、3 不规则变化 first second third 1st 2nd 3rd 4-19 基数词词尾加 th fourth fifth sixth seventh eighth ninth tenth eleventh twelfth thirteenth 4th 11th 20th 21st 22nd 23rd 24th 121st 124th 20-90 整数 ty 变为 tie 再加 th twentieth thirtieth fortieth 两位数或多位数(整数 除外)只变个位数 twenty-first one hundred and thirty-fourth 一、写出下列数字的基数词，并对比记忆写出序数词(本大题共10小题，每小题4分，共40分) 1．4 ________________, _________________ 2．10 ______________, _______________ 3．12 ___________________, ___________________ 4．15 ______________, _______________ 5．8 ______________, ________________ 6．9 _______________, _______________ 7．21_______________, ___________________ 8．72 ______________, _______________ 9．40 ________________, _________________ 10．20______________, __________________ 【答案】 1． four fourth 2． ten tenth 3． twelve twelfth 4． fifteen fifteenth 5． eight eighth 6． nine ninth 7． twenty-one twenty-first 8． seventy-two seventy-second 9． forty fortieth 10． twenty twentieth 【详解】1．4的基数词是four，序数词是fourth。故填four；fourth。 2．10的基数词是ten，序数词是tenth。故填ten；tenth。 3．12的基数词是twelve，序数词是twelfth。故填twelve；twelfth。 4．15的基数词是fifteen，序数词是fifteenth。故填fifteen；fifteenth。 5．8的基数词是eight，序数词是eighth。故填eight；eighth。 6．9的基数词是nine，序数词是ninth。故填nine；ninth。 7．21的基数词是twenty-one，序数词是twenty-first。故填twenty-one；twenty-first。 8．72的基数词是seventy-two，序数词是seventy-second。故填seventy-two；seventy-second。 9．40的基数词是forty，序数词是fortieth。故填forty；fortieth。 10．20的基数词是twenty，序数词是twentieth。故填twenty；twentieth。 二、单项选择(本大题共30小题，每小题2分，共60分) 11．—Which sentence do you like best in The Little Prince? —Maybe there are five ________ roses in the world just like you, but you’re my unique rose. A．thousand B．thousands C．thousand of D．thousands of 【答案】A 【详解】句意：——在《小王子》里你最喜欢哪句话？——也许世界上有五千朵和你一模一样的玫瑰，但你是我独一无二的玫瑰。 thousand千；thousands错误形式；thousand of错误形式；thousands of成千上万的。根据语法规则，当thousand前有具体数字时，需用单数形式，不加s，也不与of连用；thousands of前不能接具体数字，因此five thousand符合语境和语法要求，应填thousand。 12．Every year, ________ people come to visit the Great Wall. A．hundred B．hundreds C．hundred of D．hundreds of 【答案】D 【详解】句意：每年，成百上千的人来参观长城。 hundred前有具体数字时用单数，不加of；表示概数“成百上千”时用复数，且加of，即hundreds of。本句中空前没有具体数字，表示概数，应填hundreds of。 13．My grandfather is ________ years old. Today is his ________ birthday. A．ninty-nine; ninety-nineth B．ninety-ninth; ninety-nine C．ninety-nine; ninetieth-nine D．ninety-nine; ninety-ninth 【答案】D 【详解】句意：我的爷爷九十九岁了，今天是他的第九十九个生日。 第一空，表示年龄用基数词ninety-nine；第二空，表示“第几个生日”应该用序数词，ninety-nine的序数词是ninety-ninth。 14．There are _________ months in a year and May is _________ month of the year. A．twelve; the fifth B．twelve; five C．twelfth; five D．twelfth; the fifth 【答案】A 【详解】句意：一年有十二个月，五月是一年中的第五个月。 第一空表示数量，修饰复数名词months，应用基数词twelve；第二空表示顺序，指“第五个”，应用序数词fifth，且序数词前通常加定冠词the。 15．—How many teachers are there in your school?   —About ________. And ________ them are women teachers. A．three hundreds, two hundred of B．three hundred, two hundred of C．three hundred, two hundreds of D．three hundreds, two hundreds of 【答案】B 【详解】句意：——你们学校有多少老师？——大约三百名。并且其中两百名是女教师。 hundred前有具体数字时，hundred用单数形式，不加s；表示“她们中的几百个”时，用“数字+hundred+of+them”结构。第一空表示三百，用three hundred；第二空表示她们中的两百名，用two hundred of。 16．In our city, the number of the teachers________ about 2,000, but only about ________ of them are men teachers. A．is;seven hundreds B．are;seven hundred C．is;seven hundred D．are;seven hundreds 【答案】C 【详解】句意：在我们城市，教师的数量大约是2000人，但其中只有大约七百人是男教师。   根据“the number of the teachers”可知，主语是“the number of复数名词”，意为“……的数量”，谓语动词应用单数形式，故第一空用is；根据“seven hundred”可知，当hundred前有具体数字时，hundred用单数形式，不加s，故第二空用seven hundred。 17．—Neil, can you read the number 15,859? —Yes, I can. It’s ________. A．fifteen thousands eight hundred and fifty-nine B．fifteen thousand eight hundreds and fifty-nine C．fifteen thousand eight hundred and fifty-nine D．fifteen thousand and eight hundred and fifty-nine 【答案】C 【详解】句意：——Neil，你能读出 15,859 这个数字吗？——是的，我能。 英语中hundred，thousand前有具体数字修饰时，不用复数形式；thousand和hundred之间不用and连接，百位与十位之间用and连接，千位与百位之间不用and。A 项thousands多了s；B项hundreds多了s；D项 thousand后多了and。应填fifteen thousand eight hundred and fifty-nine。 18．________ of the money ________ used to help the poor children in mountain areas. A．Three-fourths; are B．Three-fourths; is C．Third-fourths; are D．Three-fourth; is 【答案】B 【详解】句意：四分之三的钱被用来帮助山区的贫困儿童。 分数表达中，分子用基数词，分母用序数词，分子大于1时分母加s，故“四分之三”为Three-fourths；“分数+of+名词”作主语时，谓语动词与of后的名词保持一致，money为不可数名词，谓语动词用单数is。故选B。 19．—Have you heard of the famous writer? —Certainly. About ________ teenagers love him very much in our school. A．hundreds B．two hundreds of C．two hundreds D．two hundred 【答案】D 【详解】句意：——你听说过那位著名作家吗？——当然。在我们学校大约两百个青少年非常喜欢他。 hundred前有具体数字时用单数形式，且后不加of；表示不确定数目时用hundreds of。根据“About ________ teenagers”可知，此处表示具体数目“两百”，two后hundred用单数。故选D。 20．There are ________ days in a year. A．three hundreds and sixty five B．three hundred and sixty five C．three hundred and sixty-five D．three hundred sixty-five 【答案】C 【详解】句意：一年有三百六十五天。 具体数字后hundred用单数形式；百位和十位之间需用and连接；十位和个位之间需用连字符连接。A项hundred误用复数，D项缺少and，C项符合规范。 21．—Can you teach me how to read the number 65,023 in English, Peter? —Yes. It’s ________. A．sixty-five thousands and twenty-three B．sixty-five thousands, twenty-three C．sixty-five thousand, twenty-three D．sixty-five thousand and twenty-three 【答案】D 【详解】句意：——彼得，你能教我怎么用英语读数字 65,023 吗？——可以。它是六万五千零二十三。 英语中hundred, thousand, million等单位词前有具体数字时不加 s，排除 A和B选项；当百位为零时，千位与十位/个位之间常用and连接，且几十几中间需加连字符，排除C选项。 22．There are ________ teachers in No. 1 Middle School. ________ of them are women teachers. A．hundreds; Two hundreds B．hundreds of; Two hundreds C．hundreds of; Two hundred 【答案】C 【详解】句意：第一中学有数百名教师，其中两百名是女教师。 hundreds of是固定搭配，意为“数百的，成百上千的”，表示不确定的数量；当“hundred”前有具体数字时，用单数形式“hundred”，不能加“s”，“Two hundred”表示“两百”。 应填hundreds of; Two hundred。 23．Which number is six hundred and seventy-three thousand one hundred and eleven? A．6,073,100 B．60,731,100 C．6,731,11 D．673,111 【答案】D 【详解】句意：哪个数字是六十七万三千一百一十一？     英语数字表达从高位到低位，“six hundred and seventy-three thousand”意为“673,000”，“one hundred and eleven”意为“111”，组合起来为673,111。 24．How do you say 3,456? A．Three thousands four hundred and fifty-six. B．Three thousand four hundred and fifty-six. C．Three thousand four hundred fifty-six. D．Three thousands four hundred fifty-six. 【答案】B 【详解】句意：你怎么读3,456? 读数时，thousand前有具体数字时不加s；百位与十位之间需加and。 25．—Look at the picture! There were so many people watching Suchao last night. — ________? That’s so amazing. A．Sixty-one thousand, one hundred and six B．Sixty-one thousand, one hundred zero six C．Sixty-one thousands, one hundred and six D．Sixty-one thousands, one hundred zero six 【答案】A 【详解】句意：——看这张照片！昨晚有那么多人在看苏超。——六万一千一百零六人？太惊人了。 hundred, thousand前有具体数字修饰时用单数形式，不加s；百位与个位之间通常用and连接，应填Sixty-one thousand, one hundred and six。 26．— Do you know how to read the big number “815,096”, David? — Yes! It’s________. A．eight hundred fifty-one thousand and ninety-six B．eighty-one thousand five hundred and ninety-six C．eight hundred and fifteen thousand and ninety-six D．eight million one hundred five thousand and ninety-six 【答案】C 【详解】句意：——大卫，你知道怎么读这个大数“815,096”吗？——知道！它是八万五千零九十六。 英文数字中，千位分隔符前依次为万、十万位，81对应eighty-one，509对应five hundred and nine，后接thousand，最后用and连接ninety-six，故正确读法为eight hundred and fifteen thousand and ninety-six。 27．My cousin will be ________ years old next month, and we plan to celebrate his ________ birthday at a fancy restaurant. A．twelve; twelve B．twelfth; twelve C．twelve; twelfth D．twelfth; twelfth 【答案】C 【详解】句意：我的表弟下个月就十二岁了，我们计划在一家高档餐厅庆祝他的十二岁生日。 twelve十二；twelfth第十二。表示年龄“多少岁”应用基数词，故第一空填twelve；表示“第几个生日”应用序数词，故第二空填twelfth。 28．—Simon, how old is your grandpa this year? —________. And we are planning a special birthday party for his ________ birthday this Sunday. A．Ninetieth; ninety B．Ninety; the ninetieth C．Ninety; ninetieth D．Ninetieth; the ninety 【答案】C 【详解】句意：——西蒙，你爷爷今年多大年纪了？  ——九十岁。我们正在计划这个星期天为他九十岁生日举办一场特别的生日聚会。 Ninetieth第九十(序数词)，ninety九十(基数词)；the ninetieth第九十(序数词)；the ninety表述错误，选项D排除。根据问句“how old is your grandpa this year”可知，提问年龄需用基数词回答；答句中“his ________ birthday”表明，空格处需用序数词表示第九十个生日，空格前有形容词性物主代词his，不需用定冠词the。选项C符合。 29．—Do you know how to read the number 5,050,179?   —Yes, I can. It is ________. A．Five millions, fifty thousands, one hundred and seventy-nine. B．Five millions, fifty thousands, one hundred seventy-nine. C．Five million, fifty thousand, one hundred seventy-nine. D．Five million, fifty thousand, one hundred and seventy-nine. 【答案】D 【详解】句意：——你知道数字5,050,179怎么读吗？——是的，我知道。它是五百零五万零一百七十九。 在英语中，当“hundred”、“thousand”、“million”等词前面有具体数字修饰时，它们用单数形式，且“百”和“十”之间一般用and连接，所以正确答案是Five million, fifty thousand, one hundred and seventy-nine.。 30．We planted ________ trees last year. Three ________ of them are in the park. A．thousands of; hundred B．thousand of; hundred C．thousands of; hundreds D．thousand of; hundreds 【答案】A 【详解】句意：去年我们种植了几千棵树，其中的三百棵在公园里。 考查数词。thousand是一个数量单位，千，它和具体的数词连用的时候，不用复数形式；或者构成短语thousands of表示约数，成千的。hundred是百，用法与thousand相同。结合选项可知，空一用thousands of表示“成千的”；由“Three”可知，空二表示具体的数字，不用复数。故选A。 31．—It is Mum’s ________ birthday next Wednesday. What should we do? —How about buying her ________ flowers to show our love? A．forty; forty B．fortieth; forty C．forty; fortieth D．fortieth; fortieth 【答案】B 【详解】句意：——下周三是妈妈的四十岁生日。我们该做些什么呢？——给她买四十朵花来表达我们的爱意，怎么样？ 考查数词。forty四十（基数词）；fortieth第四十（序数词）。根据“It is Mum’s...birthday next Wednesday.”可知，此处指妈妈的四十岁生日，即第四十个生日，第一空应是序数词fortieth；根据“buying her...flowers”可知，此处指买四十朵花，第二空用基数词forty，表数量。故选B。 32．Please turn to Page ________ and look at the ________ picture from the left. A．Ten; three B．Tenth; third C．Ten; third D．Tenth; three 【答案】C 【详解】句意：请翻到第十页，看左起第三张图。 考查数词用法。Ten十，基数词；Tenth第十，序数词；third第三，序数词；three三，基数词。表示页数时，使用“Page+基数词”，即Page Ten；表示图片的顺序时，使用“the+序数词+名词单数”，即the third picture。故选C。 33．We read 23,813 like this: ________. A．twenty-three thousands, eight hundred and thirteen B．twenty-three thousands and eight hundred and thirteen C．twenty-three thousand, eight hundred and thirteen D．twenty-three thousand, eight hundred thirteen 【答案】C 【详解】句意：我们像这样读23,813：两万三千八百一十三。 thousand前有具体数字时，用单数形式，排除A和B；百位和十位之间需用and连接，应填twenty-three thousand, eight hundred and thirteen。 34．There are ________ students in our school. Five hundred of them are boys. A．nine hundred B．nine hundreds C．nine hundred of D．nine hundreds of 【答案】A 【详解】句意：我们学校有九百名学生。其中五百名是男孩。 “hundred”前面有具体数字修饰时，用单数形式，且后面直接接名词复数，不加“of”；当表示概数“数百”时，用“hundreds of”。根据题干可知，空处前有具体数字“nine”，故用“nine hundred”直接修饰“students”。 35．There are about __________ elephants in this zoo. A．twelfth B．twentieth C．twenty D．twenties 【答案】C 【详解】句意：这个动物园里大约有二十头大象。 twelfth第十二；twentieth第二十；twenty二十；twenties二十几/二十年代。根据“There are about ... elephants”可知，此处表示大象的数量，应用基数词twenty。 36．—Excuse me, can you read the number “________” in English? —Of course. Eight million, three hundred and sixty-three thousand. A．8,360,360 B．8,660,360 C．8,363,000 【答案】C 【详解】句意：——打扰一下，你能用英语读出这个数字“8,363,000”吗？——当然可以。八百三十六万三千。 根据答语“Eight million, three hundred and sixty-three thousand”可知，million表示“百万”，thousand表示“千”。Eight million是8,000,000，three hundred and sixty-three thousand是363,000，合起来是8,363,000。 37．— Excuse me, can you tell me how to say 5,510,628 in English? — Sure. It’s ________ A．five million, five hundred ten thousand, six hundred twenty-eight B．five billion, five hundred and ten million, six hundred and twenty eight. C．five million, five hundred and ten thousand, six hundred and twenty-eight. 【答案】C 【详解】句意：——打扰一下，你能告诉我5, 510, 628用英语怎么说吗？——当然。它是five million, five hundred and ten thousand, six hundred and twenty-eight。 英文数字从高位到低位，每三位为一个单位，百位与十位之间加“and”，十位与个位之间加连字符。5, 510, 628分为5 million, 510 thousand和628三部分，510读作five hundred and ten，628读作six hundred and twenty-eight。A项缺少“and”，B 项单位错误（billion），C 项符合规则。 38．Jim will turn _________ tomorrow and there will be a party for his _________ birthday. A．twenty; twenty B．twentieth; twentieth C．twenty; twentieth D．twentieth; twenty 【答案】C 【详解】句意：吉姆明天将满二十岁，并且将为他的第二十个生日举行一个派对。 twenty二十，基数词；twentieth第二十，序数词。根据“Jim will turn...tomorrow”可知，表示年龄时，turn后接基数词；根据“there will be a party for his...birthday.”可知，表示“第几个生日”时，用序数词修饰birthday。应填twenty；twentieth。 39．Please turn to Page ________, boys and girls. Today, we are going to learn ________ unit. A．Fifth; Five B．Five; the five C．Fifth; the fifth D．Five; the fifth 【答案】D 【详解】句意：请翻到第五页，孩子们。今天我们将学习第五单元。 表示“第几页”常用“Page+基数词”结构，故第一空填Five；表示“第几单元”常用“the+序数词+名词”结构，故第二空填the fifth。故选D。 40．—If a=10, b=3, what’s the answer to the question “ab+3”?    —________. A．Sixty B．Seventy-three C．Thirty-three D．Thirty 【答案】C 【详解】句意：——如果a=10，b=3，那么问题“ab+3”的答案是什么？——三十三。 Sixty六十；Seventy-three七十三；Thirty-three三十三；Thirty三十。根据“If a=10, b=3”可知，ab表示10乘以3，即30，那么ab+3就是30加3，等于33，应填Thirty-three。 试卷第1页，共3页 试卷第1页，共3页 学科网（北京）股份有限公司 $