数词：基数
Numerals: cardinals

从第二级起你就会数一到十了，也会说二十一、三十五。你说过八点上课，说过这本书三十五块。这些数你早就会念——现在只要往上再加三个字：百、千、万。汉语的数是搭起来的：十二是十加二，二十是两个十，三百五十六还是照这个办法搭。

Since level 2 you have counted 一 to 十 and said 二十一, 三十五, 八点上课, 三十五块. Chinese numbers are assembled: 十二 is ten plus two, 二十 is two tens. Everything in this lesson is that same assembly carried three places further — 百, 千, 万.

数词很少单独修饰名词，它要先跟量词组成数量短语：三本、五个、两杯。这一步你在第三级已经练熟了，本课只管数目本身怎么念、怎么写。

A numeral almost never modifies a noun by itself: it first joins a classifier to make a 数量短语 — 三本, 五个, 两杯. You have been doing that since level 3. This lesson is about the number itself.

英语每三位一节（thousand、million），汉语每四位一节。念一个大数，先从右边数四位切一刀，前面一节念完加个万字，后面一节照常念。十万不是一个新词，是十个万；一百万是一百个万；一万个万就是一亿。

English cuts a long number every three digits — thousand, million. Chinese cuts it every four. That one fact explains everything that feels strange: 100,000 is not a new word but 十万, ten 万; 1,000,000 is 一百万, a hundred 万; and 一亿 is ten thousand 万. Count four places from the right and read the two halves separately.

这是最容易说错的一处。数数的时候念二：一、二、三；报号码、说日子也念二：二十二号、十二月。可是一到量词前面，马上换成两：两个人、两本书、两块钱、两点。千、万、亿前面也用两：两千、两万。百前面两种都有人说，二百和两百都对。

This is the commonest slip. Counting, reading a house number, giving a date — all take 二: 一、二、三, 二十二号, 十二月. The moment a classifier follows it becomes 两: 两个人, 两本书, 两块钱, 两点. 千, 万 and 亿 take 两 as well. Before 百 both are heard, and 二百 and 两百 are both correct.

零说的是位置，不是数目。一百零五里的零告诉你十位是空的；一万零三里的零一口气盖住了三个空位。零后面的数照常念。要是空位在末尾，就什么也不用说：三百就是三百，不说三百零零。

零 marks a place, not a quantity. In 一百零五 it tells you the tens place is empty; in 一万零三 a single 零 covers three empty places at once. Whatever follows is read normally. A gap at the end needs nothing: 三百 is simply 三百.