英语中的数词包括基数词和序数词两大类,它们的用法非常复杂,为了便于同学们系统地复习数词,现就初中阶段数词的基本构成作如下归纳。
一、基数词——从 1数到 N
1.1— 12的基数词是独立的单词,即: one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve
2.13— 19的基数词以 - teen结尾。如: fourteen, seventeen等,但 13, 15, 18较特殊, 13— thirteen, 15— fifteen, 18— eighteen
3.20— 90的整十位均以 - ty结尾。如: sixty, ninety,但 20, 30, 40, 50, 80较特殊, 20— twenty, 30— thirty, 40— forty, 50— fifty, 80— eighty
4.十位数与个位数之间要加连字符号“ -”,如: 28— twenty-eight, 96— ninety-six
5.百位和十位(若无十位则和个位)之间加 and,如: 148— one hundred and forty-eight, 406— four hundred and six
6. hundred(百), thousand(千), million(百万), billion(十亿)等前面即使有具体的数词,也不能在它们的后面加 s。如: 600— six hundred, 8百万— eight million
7.1000以上的数字,从后往前数每三位加一个逗号“,”第一个逗号前为千( thousand),第二个逗号前为百万( million),第三个逗号前为 billion(十亿)。英语中无“万”这个词,我们可以用“几十个千( thousand)”表示几万,“几百个千( thousand)”表示“几十万”。如: 2,510= two thousand five hundred and ten; 84,296= eighty-four thousand two hundred and ninety-six; 274,350= two hundred and seventy-four thousand three hundred and fifty
8. hundred, thousand, million用复数形式修饰名词时要用“ of+复数名词”,如:数以百计的年轻人— hundreds of young people;数以千计的书— thousands of books等,注意: hundreds/ thousands/ millions of+复数名词,其前面不能加具体的数词,但可加 several或 many。
Hundreds of new buildings have sprung up here this year.
Thousands upon thousands of people in South Africa are rising against their oppressors.
Thousands and thousands of people come to visit the city every day.
Millions of dollars have gone into the building of this factory.
二、序数词——由基数词转变而来,表示“这是第 N个”
1.口诀巧记基数词变序数词:“一、二、三,特殊记,八去‘ t’,九去‘ e’,‘ ve’要用‘ f’替,见‘ y’变成‘ i’和‘ e’,词尾加上‘ th’,若是遇到几十几,只变个位就可以。”(第一、第二、第三分别: first, second, third; eight— eighth, nine— ninth, five— fifth, twelve— twelfth, twenty— twentieth, forty— fortieth, twenty-five— twenty-fifth)
2.其余情况均在基数词后加 th。如: six— sixth, nineteen— nineteenth, hundred— hundredth, thousand— thousandth等。
3.序数词有时用缩写形式。如: first—— 1 st, twenty-six—— 26 th等。