《英语数词之讲习练》PPT课件.ppt

中考英语总复习大全 第七篇:数词, (一) 知识概要 数词用来表示人或物的数目多少和顺序。所以数词主要有两种：基数词，用于计数，如：one, two而序数词用于表示位置先后或次序，台：first second其构成法如下： 阿拉伯数字 基数词 序数词 简写序数词 1 one first 1st 2 two second 2nd 3 three third 3rd 4 four fourth 4th 5 five fifth 5th 6 six sixth 6th 7 seven seventh 7th 8 eight eighth 8th 9 nine ninth 9th 10 ten tenth 10th 11 eleven eleventh 11th 12 twelve twelfth 12th 13 thirteen thirteenth 13th 14 fourteen fourteenth 14th 15 fifteen fifteenth 15th 16 sixteen sixteenth 16th 17 seventeen seventeenth 17th 18 eighteen eighteenth 18yh 19 nineteen nineteenth 19th 20 twenty twentieth 20th 21 twenty-one twenty-first 21st 30 thirty thirtieth 30th 40 forty fortieth 40th 50 fifty fiftieth 50th 60 sixty sixtieth 60th 70 seventy seventieth 70th 80 eighty eightieth 80th 90 ninety ninetieth 90th 100 a(one)hundred hundredth 100th 104 one hundred and four hundred and fourth 104th 1000 a(one) thounsand thounsandth 1000th 10000 ten thounsand ten thounsandth 10000th 1000000 one million millionth 1000000th,基数词与序数词都有一定的构成方法，但都有特殊例外的几个字，所以除了要学会一般构成法之外，还要特别记熟一些例外。因它们在考试中出现的频率很高。,1 基数词构成结构 2199的两位数字，在10位和个位之间加连字符构成，如89-eighty-nine.的三位数字，由hundred 加and 再加二位数或未位数字，如： 101-one hundred and one, 223-two hundred and twenty-three.四位以上数字，应从个位起向前数三位加逗号，读作thousand,再数三位加第二个逗号，读作million,再数三位加逗号，读作billion，其读法如下：,1001-one thousand and one-five thousand, three hundred and eightysix要注意的是hundred, thousand, million与billion的用法。前面有别的基数词时，即若干个百、千、百万、十亿时，其本身都不要加s，如：three hundred students。, 若表示成百，成千或数百，数千时，前面不能有基数词，但其本身要用复数形式，然后+of+名词复数。如：thousands and thousands of。 (成千上万),2 序数词的构成法 序数词除first, second, third 以外，其余一般在词尾加th构成，除一般略有差异的各别数词外，很容易掌握。其二位数或多位数只将后面的个位数字改为序数词，其前面各位数字均不改变，都用基数词。,3 其他数字表示法 小数的小数点读作point，零读作o或zero,小数点后面的数字按个位基数词依次读出。分数分子用基数词，分母用序数词，当分子大于1时，分数要在序数词上加s，但用one half, 1 4 用a quarter. 读作one third而 读作two thirds。百分数(%)，读作per cent (percent),但不论是多少均用作单数形式不能加s。表示日期有两种说法和四种写法，如：2月1号英语表达法为：the first of February而美语为February (the) first,但其书写上可有四种写法 February 1 February 1st 1st February 1/2。倍数的讲法有所不同。两倍用twice,而三倍以上用序数词加times,如：He has three times as many books as I have.,(二) 正误辨析 误 1107 should be read as a thousand a hundred as seven. 正 1107 should be read as one thousand one hundred and seven. 析 在读数字时，如：and前只有百或千时，用one hundred/ one thousand 还是a hundred /a thousand全是可以的。但如果文有百又有千时，则只能用one不要用a。 如果没有and时，如：1100也只能读作one thousand one hundred 或eleven hundred.,误 I drove about half mile. 正 I drove about half a mile. 析 半小时为half an hour, 半天为half a day, 半镑为half a pound, 尽量避免用half a year, half a month, 要用six months, two weeks 或 fifteen days 要注意的是Half of the work is done Half of the books are sold. 当Half 作名词时，其谓语动词要看of后面的名词而定。如名词是不可数名词则用单数谓语动词，如是复数名词时，则要用复数谓语动词。要注意的是一个半的表达法，如：One and a half apples is left on the table.其名词要用复数，但谓语动词则要用单数。,误 60 students are playing on the ground. 正 Sixty students are playing on the ground. 析 在句首的数字要用文字而不要用阿拉伯数字，如数字过大则应放于句中，用阿拉伯数字。如： There are 166 students playing on the ground.,误 He became famous around fifty years old. 正 He became famous in his fifties. 析 in his fifties 50多岁时，而in the fiflies 在50年代。,误 There are about two th