Numbers (二 vs 两; big numbers)
A1 数词（二、两与大数） 5 / 56
In short
Chinese numbers are strictly regular: build any number from ten digits plus a few place-words (十 shí ten, 百 bǎi hundred, 千 qiān thousand, 万 wàn ten-thousand). Two things surprise English speakers: the number “two” has two forms - 二 èr for counting and 两 liǎng before a thing - and big numbers are grouped by ten-thousand (万), not by thousand.
The rule
There is no plural, no case, no agreement. A number is just digits and place-words snapped together in the same order you would read them aloud.
Step 1 - Learn the ten digits 0-10. These are the atoms of everything else (full list in the table below): 零 líng 0, 一 yī 1, 二 èr 2 … 九 jiǔ 9, 十 shí 10.
Step 2 - Build 11-99 from 十.
- Teens (11-19) = 十 + unit: 十一 shí yī (11), 十五 shí wǔ (15), 十九 shí jiǔ (19). Note 10 by itself is just 十, never 一十 - but only while nothing precedes it: once a bigger place-word stands in front, the tens digit 1 is written out again (一百一十 yī bǎi yī shí 110, 二百一十 èr bǎi yī shí 210), never 二百十.
- Tens (20, 30 …) = unit + 十: 二十 èr shí (20), 三十 sān shí (30), 九十 jiǔ shí (90).
- In between = unit + 十 + unit: 二十五 èr shí wǔ (25), 九十九 jiǔ shí jiǔ (99).
Step 3 - Add the big place-words. For hundreds and up, say multiplier + place-word, then keep chaining from the largest place down to the smallest: 三百 sān bǎi (300), 五千 wǔ qiān (5,000), 两万 liǎng wàn (20,000). Unlike 十, the words 百 / 千 / 万 always need a multiplier in front: 100 is 一百 yī bǎi (never bare 百), 1,000 is 一千, 10,000 is 一万.
Step 4 - Group by 万, not by thousand. This is the big-number trap. English commas cut a number every 3 digits (thousand, million, billion); Chinese cuts every 4 digits, at 万. So there is no single word for “million” - a million is 一百万 yī bǎi wàn (“a hundred ten-thousands”). The next fresh place-word after 万 is 亿 yì = 100,000,000 (a hundred million). To read a big number, mentally re-comma it into groups of four from the right.
Step 5 - Fill internal gaps with 零. When a number has a zero inside it, you must say 零 líng as a placeholder: 一百零五 yī bǎi líng wǔ (105), 一千零一 yī qiān líng yī (1,001). A whole run of consecutive zeros is covered by a single 零: 一千零五 yī qiān líng wǔ (1,005). Zeros at the end are simply dropped: 150 is 一百五十 yī bǎi wǔ shí, with no 零.
Step 6 - Choose 二 or 两 for “two”. Both mean 2, but they are not interchangeable:
- Use 二 èr for counting, arithmetic, and any digit sitting in the tens or ones slot of a number: 二 (2), 十二 (12), 二十 (20), 二十二 (22).
- Use 两 liǎng for “two of something” - directly before a measure word (两个 liǎng ge, “two [of them]”) and before the big units 千 / 万 / 亿 (两千, 两万). The full number + measure + noun pattern belongs to Measure words (classifiers); here just remember that the “2” in front of a measure word is 两, not 二.
- Before 百, both are fine: 二百 or 两百 (200).
Forms & patterns
The ten digits:
| # | 汉字 | Pinyin | # | 汉字 | Pinyin |
|---|---|---|---|---|---|
| 0 | 零 | líng | 6 | 六 | liù |
| 1 | 一 | yī | 7 | 七 | qī |
| 2 | 二 | èr | 8 | 八 | bā |
| 3 | 三 | sān | 9 | 九 | jiǔ |
| 4 | 四 | sì | 10 | 十 | shí |
| 5 | 五 | wǔ |
Place-words and the ten-thousand ladder (note where English and Chinese words fall):
| Number | 汉字 | Pinyin | English |
|---|---|---|---|
| 100 | 一百 | yī bǎi | one hundred |
| 1,000 | 一千 | yī qiān | one thousand |
| 10,000 | 一万 | yī wàn | ten thousand |
| 100,000 | 十万 | shí wàn | one hundred thousand |
| 1,000,000 | 一百万 | yī bǎi wàn | one million |
| 10,000,000 | 一千万 | yī qiān wàn | ten million |
| 100,000,000 | 一亿 | yī yì | one hundred million |
二 vs 两 at a glance:
| Context | Use | Example | Pinyin |
|---|---|---|---|
| Counting, arithmetic | 二 | 一、二、三 | yī, èr, sān |
| Tens / ones digit in a number | 二 | 二十二 | èr shí èr (22) |
| Reading digits one by one | 二 | 二〇二 | èr líng èr |
| Before a measure word | 两 | 两个 | liǎng ge (two [of]) |
| Before 千 / 万 / 亿 | 两 | 两万 | liǎng wàn (20,000) |
| Before 百 | 二 or 两 | 二百 / 两百 | èr bǎi / liǎng bǎi (200) |
Examples
- 一、二、三，我们开始。 (Yī, èr, sān, wǒmen kāishǐ.) - One, two, three, let’s begin.
- 二十加二十是四十。 (Èr shí jiā èr shí shì sì shí.) - Twenty plus twenty is forty.
- 一年有三百六十五天。 (Yī nián yǒu sān bǎi liù shí wǔ tiān.) - A year has three hundred sixty-five days.
- 一百零五。 (Yī bǎi líng wǔ.) - One hundred and five.
- 一千零一夜。 (Yī qiān líng yī yè.) - One Thousand and One Nights.
- 一万有四个零。 (Yī wàn yǒu sì ge líng.) - Ten thousand has four zeros.
- 中国有十四亿人。 (Zhōngguó yǒu shí sì yì rén.) - China has one point four billion people.
- 我要两个。 (Wǒ yào liǎng ge.) - I want two (of them).
- 两百人还是二百人都行。 (Liǎng bǎi rén háishi èr bǎi rén dōu xíng.) - Whether you say liǎng bǎi or èr bǎi for two hundred people, either is fine.
Common mistakes
- 二个 -> 两个 (liǎng ge, two of them) - right before a measure word “two” is always 两, never 二.
- 两十 -> 二十 (èr shí, 20) - inside a number the “2” digit is 二; 两 never fills the tens or ones slot.
- 一百五 (meaning 105) -> 一百零五 (yī bǎi líng wǔ, 105) - an internal zero needs 零; 一百五 is read as 150.
- 一千零零五 -> 一千零五 (yī qiān líng wǔ, 1,005) - one 零 covers a whole run of zeros, however many.
- 一百千 (calquing “one hundred thousand”) -> 十万 (shí wàn, 100,000) - Chinese has no “thousand” grouping above 千; count in 万.
Tips
- Re-comma big numbers by fours from the right, not threes. 1,234,567 regroups as 123,4567 = 一百二十三万四千五百六十七 - read the 万 group, say 万, then read the rest.
- Rule of thumb for “two”: 两 = “two things” (before a measure word or 千/万/亿); 二 = “the number 2” (counting, tens, ones, digits, math). 百 tolerates both.
- The tone of 一 shifts in speech (sandhi): it is yī on its own and when reciting digits, but becomes yì before a 1st, 2nd or 3rd tone (一百 yìbǎi, 一千 yìqiān) and yí before a 4th tone (一万 yíwàn, 一亿 yíyì). The character never changes; only the sound does.
- Reading digit strings like phone or room numbers, say each digit separately, keep 二 (not 两), and note that 一 is often pronounced yāo there so it is not misheard as 七 qī.