num. 千a. 成千的, 许多的n. 许许多多相关词组: a thousand times easier than in a thousand and one ways a thousand to one by the thousand one in a thousand the upper ten thousand

◆记忆方法一：
联想方式：thou—太后 sand—沙子
送给太后一千颗沙子
◆记忆方法二：
分析：thou——“太后”的拼音首字母；sand——沙子
记忆方法：我送给太后的礼物是一千粒沙子

◆记忆方法三：
联想方式：thou—太后 sand—沙子
记忆方法：送给太后一千颗沙子

• hundred, thousand和million的用法
  
  (1) 用单数的场合
  当这些词与具体数字连用时，习惯上用单数，而且也不后接介词of。如：
  He was prepared to pay two million. 他愿意支付200万。
  More than a hundred people were injured. 有一百多人受了伤。
  但是，当这些词后面的名词有了the, these, those等特指限定词修饰时，或其后的接的是us, them 这样的人称代词时，则此时必须用介词 of。如：
  About three hundred of them have left there. 他们当中约有300人离开了那儿。
  (2) 用复数的场合
  当这些词不与具体数字连用，而是表示不确定的泛指数时，则不仅要要用复数，而且要后接介词of，然后才能接名词。如：
  The sun was shining. Thousands of people were lying on the beach. 阳光灿烂，数以千计的人躺在海滩上。

billion/million/millionaire/thousand/hundred/dozen/score
记忆：
1. billion bill-ion联想Bill Gates, 世界亿万富翁；billion, 十亿
2. million mill-ion 百万
3. millionaire n. 百万富翁 Nowadays a millionaire is no longer an attraction in newspapers. 今天百万富翁不再是报纸上的亮点。
4. thousand千 Thousands of people went to the street to show their call for peace. 成千上万的人走上街头呼唤和平。
5. hundred 百
6. dozen音“打”， 一打，十二 We brought home two dozen beer. 我们带了两打啤酒回家。
7. score sc两个“十”， 二十， 得分 He bought two score of apples yesterday.他昨天买了四十个苹果。
另类阅读：
Beer is sold by the dozen here. I want five score of bottle, but I have only one hundred yuan. If you can lend me one million, I can have thousands of yuan left. I could say billion, for it is impossible.