定義：表示數目多少或順序多少的詞叫數詞，數詞分為基數詞和序數詞。表示數目多少的數詞叫基數詞;表示順序的數詞叫序數詞。下面是本站小編精心為大家整理的關於數詞的國中英語語法，希望對大家有幫助，更多內容請關注應屆畢業生網!
I基數詞
1.基數詞的構成
(1)1-20
one,two,three,four,five,six,seven,eight,nine,ten,eleven,twelve,thirteen,fourteen,fifteen, sixteen, seventeen, eighteen, nineteen, twenty
(2)21-99 先說“幾十”，再說“幾”，中間加連字元。
23→twenty-three,34→thirty-four,45→forty—five,56→fifty-six,67→sixty-seven,78→seventy-eight,89→eighty-nine,91→ninety-one
(3)101—999先說“幾百”，再加and,再加末兩位數或末位數;
586→five hundred and eighty-six,803→eight hundred and three
(4)l,000以上,先從右往左數，每三位數加一個“,”,第一個“,”前為thousand.第二個“,”前為
million,第三個“,”前為billion(美式)或thousand ,million(英式),然後一節一節地表示。
1,001→one thousand and one
9,785→nine thousand, seven hundred and eighty-five
18,423→eighteen thousand, four hundred and twenty-three
6,260,309→six million two hundred and sixty thousand three hundred and nine
750,000,000,000→seven hundred and fifty, billion(美式) seven hundred and fifty thousand million(英式)
2.基數詞的用法
(1)作主語
Of them come from Paris.
(2)作賓語
eg.一 How many books would you like?
一I would like two.
(3)作表語
n minus two is five.
(4)作定語
e are three people in my family•
(5)作同位語
eg. You two will go swimming with us.
(6)表具體數字時,hundred, thousand ,million用單數。
eg. There are six hundred students in our grade.
(7)表不確定的數字時,數詞用複數。若帶名詞，再加of。 hundreds of(數百,成百上千的),thousands of(數幹,成千上萬的),millions of(數百萬)two thousand (兩千)
Thousands and thousands of people have visited the city.成千上萬的人蔘觀了這座城市。
(8)在一些表示“一排”或“一組”的詞組裡;
eg,They arrived in two sand threes.他們三三兩兩地來了。
(9)表示“…十”的數詞的.複數可以表示人的歲數或年代。
eg. He is in his early thirties.他有三十來歲(31—34歲)：
This took place in the 1930s.這事發生在二十世紀三十年代;
(10)表示時刻
鐘點表達法。
順讀法(鐘點+分鐘) 如：4:30 four thirty 4:45 four forty-five 4:15 four fifteen 倒讀法(分鐘+to/past+鐘點)
如：4:30 half past four
4:15 fifteen past four/a quarter past four 4:45 fifteen to five/a quarter to five
eg.I watch CCTV News at seven o’clock every evening.
(11)表示百分數
百分數的表達方式是：基數詞+ percent(單數形式)+of+名詞。如：
Thirty percent of the students in my class are from cities. 我班30%的學生來自城市。
About 61 percent of the surface is covered by water. 大約61%的表面被水覆蓋著。
(12)小數的讀法：小數點讀作"point"，小數後各位數要分別讀， 小數點前的數若為"0"可略去不讀。
Examples： 2.468 讀作：two point four six eight
0.157 讀作：(zero)point one five seven
II 序數詞
1.序數詞的構成
(1)一般在基數詞後加th
→fourth,thirteen→thirteenth
(2)不規則變化
one→first, two→second, three→third, five→fifth,eight→eighth,
nine→ninth,twelve——twelfth
(3)以y結尾的十位整數，變y為ie再加th
twenty→twentieth, forty→fortieth, ninety→ninetieth
(4)從二十一後的“幾十幾”直至“幾百幾十幾”或“幾千幾百幾十幾”只將個位的基數詞變為序數詞。
twenty-first,two hundred and forty-fifth
2.序數詞的用法
(1)序數詞作定語時，一般要與定冠詞或物主代詞連用。
is their second son.
He is the first one to come here.
(2)序數詞有時可與不定冠詞連用，表示數量上“又—”,“再一”
eg： He tried a second time.他又試了—次。
Shall l ask him a third time?還要我再問他—次嗎?我已問了他兩次)
(3)序數詞的縮寫形式為：阿拉伯數字加上這個詞的末尾兩個字母。
1st 2nd,3rd,4th,20th,21st,22nd,23rd
(4)表示年、月、日時，年用基數詞，日用序數詞。
2005年8月15日：(英)15,8,2005=15th,August,2005;(美)8,15,2005=August 15th,2005
III基數詞和序數詞都可以用來給數字編號
The first lesson=Lesson Two(第二課)
第305房間：Room three o(零)five
長安街76號：seventy-six Changan Street
電話號碼：204-2244：telephone number two o(零) four two two(double two four four
十一路公共汽車：Bus(No.) eleven
IV分數詞的表達
分子用基數詞，分母用序數詞，分子大於1時，分母加s
eg.1/3-one third;2/5-two fifths
V數學運算的表達
eg.3+5=8 Three plus/and five is eight.
9-2=7 Nine minus two is seven.
6x5=30 Five times six is thirty /six unutilized five is thirty.
8÷2=4 Eight divided by two is four.
VI倍數表示法
a. 主語+謂語+倍數(或分數)+ as + adj. + as
I have three times as many as you. 我有你三倍那麼多。
b. 主語+謂語+倍數(分數)+ the size (amount，length…) of…
The earth is 49 times the size of the moon. 地球是月球的49倍。
c. 主語+謂語+倍數(分數)+ 形容詞(副詞)比較級+ than…
The grain output is 8 percent higher this year than that of last year.
今年比去年糧食產量增加8%。
d. 還可以用by+倍數，表示增加多少倍
The production of grain has been increased by four times this year.
今年糧食產量增加了4倍。
