不定冠词、序数词、倍数表示法、分数表示法

1. 国名，人名前通常不用定冠词：England，Mary 抽象名词表示一般概念时，通常不加冠词；
　 Failure is the mother of success.　失败乃成功之母。在称呼或表示官衔，职位的名词前不加冠词；
　 The guards took the American to General Lee.

2. 当名词前的形容词被副词as, so, too, how, however, enough修饰时，不定冠词应放在形容词之后：
　　 It is as pleasant a day as I have ever spent.
　　 So short a time.
　　 Too long a distance.

3. 序数词的缩写形式： first---1st　second---2nd　thirty-first---31st　

4. 倍数表示法
a. 主语+谓语+倍数（或分数）+ as + adj. + as
　　　 I have three times as many as you.　我有你三倍那么多。

b. 主语+谓语+倍数（分数）+ the size (amount，length…) of…
　　　 The earth is 49 times the size of the moon.　地球是月球的49倍。

c. 主语+谓语+倍数（分数）+ 形容词（副词）比较级+ than…
　　 The grain output is 8 percent higher this year than that of last year.
　　 今年比去年粮食产量增加8%。
d. 还可以用by+倍数，表示增加多少倍
　　 The production of grain has been increased by four times this year.
　　 今年粮食产量增加了4倍。

5. 2）分数表示法
　　构成：基数词代表分子，序数词代表分母。分子大于1时，分子的序数词用单数，分母序数词用复数：
　  1/3 one-third ； 3/37 three and three-sevenths.