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新教材七年级下册知识点梳理7BUnit One语法归纳
语法归纳
（一）Cardinal numbers
A.基数词的写法：
⑴“几十几”十位和个位之间用“—”。e.g. 32 thirty-two
⑵101—999 百位和十位间加“and”.e.g. 928 nine hundred and twenty-eight
⑶1000 以上的数，从后往前每三位一段，倒数第一个数读 thousand，倒数第二个数读 million，依次类推。e.g. 8,542,601 eight million, five hundred and forty-three thousand, six hundred and one
B .基数词的运用：
1. hundred, thousand, million, billion 等前有数字修饰表示“精确数”一般用单数，但表示不定数目用复数：hundreds of; thousands of; millions of
注意区别：three hundred students;
hundreds of students;
three hundred of the students
2. 表示“几十”的数词，其复数形式可以表示年龄或年代。
e.g. in his twenties in the thirties the 1990s
3. 表示房间号、公共汽车号、电话号码、页数、年龄等用基数词，如：Room 801; No. 1 Bus; Page 44; two o’clock; a twelve-year-old girl
4. 一些计算或分数、百分数等，如：
Two plus two is four.
Five times six is thirty.
a half; a third; a quarter; three quarters; one-eighth; seven-eighths;
thirty percent
5. 年月日中，年用基数词；日用序数词
January 18, 2014; 18th January 2014
6. 基数词表
0 zero 10 ten 20 twenty 100
1 one 11 eleven 30 thirty one hundred
2 two 12 twelve 40 forty 1,000
3 three 13 thirteen 50 fifty one thousand
4 four 14 fourteen 60 sixty 10,000
5 five 15 fifteen 70 seventy ten thousand
6 six 16 sixteen 80 eighty 100,000
7 seven 17 seventeen 90 ninety one hundred thousand
8 eight 18 eighteen 1,000,000
9 nine 19 nineteen one million
（二）Ordinal numbers
序数词的运用：
1. 表示日期：e.g. 6 月 1 日 on the first of June/ on June (the) first
2. 表示编号：e.g. Lesson 5=the fifth lesson
3. 表示名次，起副词作用，前无“the” e.g. Simon came first in the English exam.
4. 序数词前有限定词修饰时，不加“the”. e.g. This is my first lesson.
5. 表示次序或楼层，如：
He is always the first to come to school in our class.
Wilson lives on the twelfth floor.
6. a/an+序数词 ，表示“又一、再一”；
I’d like a second try.
7. 序数词表
Ordinal numbers Ordinal numbers
1st=first 10th=tenth
2nd=second 11th=eleventh
3rd=third 12th=twelfth
4th=fourth 13th=thirteenth
5th=fifth 20th=twentieth
6th=sixth 21st=twenty-first
7th=seventh 22nd=twenty-second
8th=eighth 23rd=twenty-third
9th=ninth 30th=thirtieth
