As you probably already know, in Chinese, the characters 二 (èr) and 两 (liǎng) both mean “two”, however, Chinese students often get confused about when to use one or the other in a sentence.
二 (èr)
The character 二（èr) is generally used in “counting” and in 2-digit numbers (1-100). So this means we use it when we count or express both ordinal or cardinal numbers.
For example:
1. 一二三 (yī èr sān) = one two three
2. 二十二 (èr shí èr) = twenty-two
3. 第一、第二、第三 (dì yī, dì èr, dì sān) = first, second, third
4. 二楼(èr lóu) = the second floor
两(liǎng)
When it comes to measuring, when we want to express a quantity and when we need to say “two of something” we will use 两 (liǎng). As you can see it always comes before a measure word.
For example:
1. 两个人(liǎng gè rén) = two people
2. 两个月(liǎng gè yuè) = two months
3. 两本书 (liǎng běn shū) = two books
For counting numbers from 1 to 100 you will use 二. however, when expressing bigger numbers, such as 千 (qiān ) a thousand, 万 (wàn) ten thousand or “亿”(yì) hundred million, “两” is much more frequently used.
For example：
200 两百 (二百 is also used)
2000 两千
20000 两万
1222 一千两百二十二
Another potentially confusing example is the case of “2 o’clock”.
According to the general rule, we should say “二点”, However the correct way to express this is actually 两点(liǎng diǎn). An easy trick to remember this might be to think of 点 (literally “point”) as a quantity for points on the clock, if so, you would automatically say 两点(liǎng diǎn).
Post time: Apr-30-2020