English ordinals are a mess of irregulars — first, second, third, fifth, ninth, twentieth — that you simply have to memorise. Chinese has none of that. You take any cardinal number and glue 第 (dì) on the front: 第一 (first), 第二 (second), 第三十五 (thirty-fifth). One prefix, zero exceptions. The number itself never changes shape, so once you can count you can already rank. Two small details complete the picture: ordinals keep their measure word, and 第 quietly disappears in certain labelled contexts.
第 + number = ordinal, with the measure word kept
第 turns the following cardinal into "the Nth." When the ordinal counts a noun, the measure word stays — 第 + number + measure word + noun — because 第一个 is still a number phrase and still needs its classifier (measure words are obligatory).
这是我第一次来北京。
zhè shì wǒ dì-yī cì lái Běijīng
This is my first time in Beijing. — 第一次, the ordinal for 'time/occasion'.
我坐第一个，你坐第二个。
wǒ zuò dì-yī ge, nǐ zuò dì-èr ge
I'll take the first one, you take the second. — ordinal + 个.
请翻到第五页。
qǐng fān dào dì-wǔ yè
Please turn to page five. — 第五页.
这已经是第三十五届电影节了。
zhè yǐjīng shì dì sānshíwǔ jiè diànyǐngjié le
This is already the 35th film festival. — 第三十五, big ordinals work identically.
她这次考了第一名。
tā zhè cì kǎo le dì-yī míng
She came first this time. — 第一名, ranking with 名.
| Cardinal | Ordinal | Pinyin | Meaning |
|---|---|---|---|
| 一 | 第一 | dì-yī | first |
| 二 | 第二 | dì-èr | second (二, not 两) |
| 三 | 第三 | dì-sān | third |
| 十 | 第十 | dì-shí | tenth |
| 三十五 | 第三十五 | dì sānshíwǔ | thirty-fifth |
| 一百 | 第一百 | dì yìbǎi | hundredth |
When 第 is dropped: labelled slots, not rankings
Not every number-before-a-noun is a true ranking. Chinese omits 第 when the number acts as a fixed label or name rather than a position in a sequence — floors, grades, room numbers, class numbers, dates and clock times all take a bare cardinal.
我们住在二十三楼。
wǒmen zhù zài èrshísān lóu
We live on the 23rd floor. — 二十三楼, no 第; the floor is a label.
我儿子今年上三年级。
wǒ érzi jīnnián shàng sān niánjí
My son is in third grade this year. — 三年级, bare number.
今天是六月一号。
jīntiān shì liù yuè yī hào
Today is June 1st. — dates use a bare cardinal + 号, never 第.
他在三班，我在五班。
tā zài sān bān, wǒ zài wǔ bān
He's in Class 3, I'm in Class 5. — 三班, a class label.
The logic is worth internalising: 第 marks a genuine rank ("the Nth in an ordered sequence"), while a bare number often just names a slot the way English "Room 3," "Floor 2," or "June 1" does — there, English drops "-th" too. That's why 二楼 is "floor two," not "the second floor as opposed to the first," and why 一月 is simply "January," a name, not "the first month" in a ranking sense. For the fuller list of these label uses, see floors, grades and dates.
| Context | Form | Pinyin | Meaning |
|---|---|---|---|
| Floor | 二楼 | èr lóu | 2nd floor / floor two |
| Grade | 三年级 | sān niánjí | third grade |
| Date | 一号 / 五月四号 | yī hào / wǔ yuè sì hào | the 1st / May 4 |
| Class / group | 二班 | èr bān | Class 2 |
| Bus / room No. | 三号 | sān hào | No. 3 |
Common Mistakes
1. Using 两 in an ordinal. Ordinals take 二, always.
❌ 请看第两页。
Incorrect — ordinals use 二: 第二页.
✅ 请看第二页。
qǐng kàn dì-èr yè
Please look at page two. — 第二, never 第两.
2. Dropping the measure word after an ordinal. "The first person [in line]" still needs its classifier.
❌ 排在第一人是谁？
Incorrect — the ordinal keeps its MW: 第一个人.
✅ 排在第一个的是谁？
pái zài dì-yī ge de shì shéi?
Who's the first one in line? — 第一个 keeps 个.
3. Adding 第 to a date. Dates are labels, not rankings.
❌ 今天是六月第一号。
Incorrect — dates take a bare number: 六月一号.
✅ 今天是六月一号。
jīntiān shì liù yuè yī hào
Today is June 1st. — no 第 in a date.
4. Dropping 第 for "the Nth time". Without 第, 二次 means "secondary," not "the second time."
❌ 这是我二次来上海。
Incorrect — 'the second time' needs 第: 第二次.
✅ 这是我第二次来上海。
zhè shì wǒ dì-èr cì lái Shànghǎi
This is my second time in Shanghai. — 第二次.
Key Takeaways
- Prefix 第 to any cardinal for the ordinal: 第一, 第二, 第三十五 — no irregular forms to learn.
- The measure word stays: 第一个人, 第三次, 第五页.
- Ordinals always use 二, never 两 — and 第一's 一 keeps its first tone (dì-yī, no sandhi).
- 第 is dropped where the number is a label: 二楼 (floor 2), 三年级 (grade 3), 一号 (the 1st), 二班 (Class 2).
- The test: a true rank takes 第; a name for a fixed slot takes a bare number, just as English drops "-th" in "Room 3."
Now practice Chinese
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Chinese→Related Topics
- 二 vs 两HSK 1 — Chinese has two words for 'two': 二 (èr) is the counting digit — used in ordinals, tens, years and decimals — while 两 (liǎng) means 'two of something' before a measure word and before 千/万/亿.
- Floors, Grades & Ordinal Contexts (二楼, 三年级)HSK 1 — A whole family of 'position' words — floors (二楼), school grades (三年级), classes (三班), window/line numbers (五号, 一号线) — use a bare cardinal with an ordinal meaning and no 第, and they take 二, never 两.
- 0–10HSK 1 — The eleven building blocks of the whole number system: 零 0, 一 1, 二 2, 三 3, 四 4, 五 5, 六 6, 七 7, 八 8, 九 9, 十 10 — with the tones that trip learners up (四 sì vs 十 shí) and the 二/两 split for 'two'.
- Why Classifiers Are ObligatoryHSK 1 — Whenever you count a noun or point at it, Chinese demands a measure word between the number/demonstrative and the noun — 三本书, not 三书 — because a bare Chinese noun names a kind of thing, not a countable unit, so a classifier is what packages it into countable units.