一、基数词的构成
I II III IV
1 one
2 two
3 three
4 four
5 five
6 six
7 seven
8 eight
9 nine
10 ten 11 eleven
12 twelve
13 thirteen
14 fourteen
15 fifteen
16 sixteen
17 seventeen
18 eighteen
19 nineteen 20 twenty
30 thirty
40 forty
50 fifty
60 sixty
70 seventy
80 eighty
90 ninety 100 a (one) hundred
1,000 a thousand
10,000 ten thousand
1,000,000
a million
1,000,000,000
a billion(美)
a thousand million(英)
1,000,000,000,000
a trillion(美)
a billion(英)
注意:一般情况下基数词为单数形式,基数词在特殊情况下可以用复数形式:
1.hundred、thousand、million等基数词前边没有数字和“a few”、“one”、“ten”等其他限定词修饰时可用复数形式,后面再加“of+名词”,表示不确定的数,例如:hundreds of (数以百计的),thousands and thousands of (成千上万的),millions of (数以百万计的)。
2.在一些表示“一排”或“一组”的介词词组里,例如:They arrived in twos and threes.他们三三两两地到达了。
3.表示人的岁数(以“in +the +表示‘几十’的基数词的复数形式”结构表示)或年代。例如:He is in his thirties. It took place in the 1950''s(s前的“''”可以不要).
表示数量的名词dozen(n.一打, 十二个)和score(n.二十)的用法可以同基数词的用法类比。
二、序数词的构成
阿拉伯数字 基数词 序数词 序数词缩写形式 阿拉伯数字 基数词 序数词 序数词缩写形式
1 one first 1st 11 eleven eleventh 11th
2 two second 2nd 12 twelve twelfth 12th
3 three third 3rd 13 thirteen thirteenth 13th
4 four fourth 4th 14 fourteen fourteenth 14th
5 five fifth 5th 15 fifteen fifteenth 15t
6 six sixth 6th 16 sixteen sixteenth 16th
7 seven seventh 7th 17 seventeen seventeenth 17th
8 eight eighth 8th 18 eighteen eighteenth 18th
9 nine ninth 9th 19 nineteen nineteenth 19th
10 ten tenth 10th 20 twenty twentieth 20th