2. Both of the rules are broken. I want to buy a ______ one.　

　　　 A. three　　　　　 B. third　　　　　 C. forth　　　　 D. /

　3). --- Which is the smallest number of the four?　　　　　 --- _________.

　　　 A. Two- thirds　　 B. A half　　　 C. A quarter　　 D. Three-fourths

　4). Please write down the new words in the text of _______.

　　　 A. Lesson Eleven　 B. the Lesson Eleven　 C. Lesson Eleventh

　解析：1.基数词hundred, thousand, million, billion 等前有具体数字时，它们后面不能加s,若这些词后面有介词of (几百，成百上千) ，thousands of (几千，数千个)，millions of, billions of 前不可用数词修饰。但可用many, some, several 等修饰。故选答案D.

1. _______ Chinese are looking for ways to learn English well before Beijing　 2008 Olympic.　　　　　　

　 A. Thousand　　　 B. Thousands　　　 C. Thousand of　　 D. Thousands of

9．其他用法：

　1)基数词+单数名词+形容词构成合成形容词。如：一个五岁的男孩a five-year-old boy；　

　　 一座800米长的桥an 800-metre-long bridge；女子400米接力girls'400-metre relay race。

　2)具体数词+metre(s)／kilometre(s)／kilo(s)long ／ high ／tall ／deep ／away等。如：长江长6300公里。The Changjiang River is 6，300 kilometres long．

　3)表示"几十岁"用序数词，eg. 在他三十几岁时　 in his thirties

　4)倍数的表达：(一倍用once，两倍用 twice，两倍以上用基数词+times。如：5倍five times)。　

　例如：He is as tall a boy as I.

　He is a head taller than I .

　He is two years older than I

　China is four times as large as Europe.

　I am twice as old as you. (=I am twice older than you. /I am twice the age of you.)

　My books are twice as many as yours.

　China is four times larger than Europe.(=China is four times the size of Europe.)

　I pay twice as much as it was worth.

　I pay twice as much for the house.

　例题解析：举一反三，学的更轻松！

12.135 twelve point one three five 　　　　　　　　　

8．表示有小数的词用基数词。 　　　　　　　　　　　

7．表示百分数

　5℅：five percent (per cent)， 0.8℅ zero point eight percent (per cent).

12.135 twelve point one three five

5.5 five point five 　　　　　　　　　　

6. 表示有小数的词用基数词。 　　　　　　　　　　　

5．分数的表达：

　分子用基数词，分母用序数词，分子大于"1"，分母则加"s"。如：1／3 one third，2／3two thirds；　

　另外：1／2 a(one)half; 1／4one fourth或a(one)quarter;3／4threefourths或three quarters。

　　 half a second; a quarter of a second四分之一秒