langNote

Day 8: Numbers — both systems

two number systems · which one when · counters · grouping by 만 · money · 35 min

Korean has two complete sets of numbers, and you need both. This is not a curiosity — it decides whether you can buy a coffee.

하나 둘 셋 (native) and 일 이 삼 (Sino-Korean, from Chinese) are not formal and informal versions of each other. Each one is compulsory in different places, and one very common phrase uses both at once:

세 시 삼십 분three thirty. Native for the hour, Sino for the minutes.

Section 3 is the rule that decides. Learn that before you memorise anything else.

1. Sino-Korean numbers — 일 이 삼

Borrowed from Chinese, and regular all the way up.

16
27
38
49
510

Building past ten — pure arithmetic

11십일ten-one
20이십two-ten
35삼십오three-ten-five
99구십구
100
1,000
10,000

This is the most regular number system you will ever learn. No teens, no irregular tens, no backwards numbers (as German has). 48 = 사십팔 and there is nothing else to know.

⚠️ You do not say 일백 or 일천 for 100 and 1,000 — just , . But you do say 일만 for 10,000 in careful speech, and in casual speech.

2. ⚠️★ Korean groups by ten thousand

### English breaks numbers every 3 digits. Korean breaks them every 4.
English thinksKorean says
10,000ten thousand (one unit)
100,000a hundred thousand십만 (ten 만)
1,000,000a million백만 (a hundred 만)
10,000,000ten million천만
100,000,000a hundred million

This is genuinely hard, and it is hard for Koreans learning English too — the two languages chop numbers in different places.

The trick: stop translating and re-anchor on 만. Learn 만 = 10,000 as a unit in its own right, the way you know "dozen" without converting. Then 백만 is just "a hundred of those" and you never touch the word million.

⚠️ This matters daily because of money. A cheap lunch is 팔천 원 (8,000 won), a meal out is 만 오천 원 (15,000), a monthly rent is 백만 원 (1,000,000). You will hear 만 in every price.

3. ★★ Which system, when

### Sino 일이삼 — money, dates, minutes, phone numbers, anything counted above 99### Native 하나둘셋 — age, hours on the clock, and counting objects
Use Sino forUse Native for
money오천 ★ age스물다섯
year, month, date이천이십육 ★ hours
minutes삼십 counting things커피 두
phone numbers공일공…people
addresses, floorstimes, repetitions
school year학년

The clock is the one that uses both:

세 시 삼십 분 — 세 (native) 시 · 삼십 (Sino)일곱 시 십오 분 — seven fifteen

⚠️ Do not say 삼 시 or 세십 분. The hour is always native, the minute always Sino, in the same breath. Say 세 시 삼십 분 out loud ten times now — it is the phrase that makes the split permanent.

4. Native Korean numbers — and they change shape

1하나6여섯
27일곱
38여덟
49아홉
5다섯10

Tens: 20 스물 · 30 서른 · 40 마흔 · 50 · 60 예순 · 70 일흔 · 80 여든 · 90 아흔 Combining: 11 열하나 · 25 스물다섯 · 42 마흔둘

⚠️ Native numbers stop at 99. From 100 up, everyone uses Sino — even for things that would normally take native.

★ And five of them change before a counter

This is not optional. The bare form is wrong in front of a counter.
AloneBefore a counter
하나한 개, 한 명, 한 시
두 개, 두 잔
세 시, 세 명
네 살, 네 개
스물스무스무
하나, 둘, 셋 when counting out loud. 한 개, 두 개, 세 개 when counting things.⚠️ 스무 살, never 스물 살 — and 25 is 스물다섯 살, because only the bare 스물 changes.

5. ★ Counters — you cannot count without one

Korean does not say "two coffees". It says "coffee, two cups" — you must name the kind of thing you are counting.

### Noun + Number + Counter — and that order is not English's.
CounterForExample
★ general things — the fallback사과 세 개 (three apples)
people학생 두 명
people, polite손님 세 분
cups, glasses커피 두 잔
bottles맥주 한 병
마리animals두 마리
books한 권
flat sheets — paper, tickets두 장
machines, cars한 대
times, occasions세 번
years of age스무 살
시 / 분hours (native) / minutes (Sino)세 시 십 분

When you do not know the counter, use 개. It is wrong for people and animals and fine for almost everything else, and nobody will misunderstand you.

⚠️ Use 분, not 명, for customers, guests and anyone older. A restaurant will ask 몇 분이세요? (how many of you?) — the answer is 두 명이요 or 두 명입니다.

6. Numbers in the wild

Money — 원

얼마예요?How much is it?
오천 원이에요.It's 5,000 won
만 오천 원이에요.It's 15,000 won
너무 비싸요.Too expensive
깎아 주세요.Please give me a discount

Phone numbers — Sino, digit by digit

010-2345-6789공일공 이삼사오 육칠팔구

Zero is 공 in phone numbers (and 영 in maths). And often becomes after a consonant sound — do not be thrown by it.

Ordering

커피 두 잔 주세요. — Two coffees, please.맥주 세 병 주세요. — Three beers, please.몇 개예요? — How many? · 몇 명이에요? — How many people?

7. Dialogue

직원: 어서 오세요! 몇 분이세요?Alex: 두 명이요.직원: 네, 이쪽으로 오세요. 뭐 드릴까요?Alex: 커피 두 잔 주세요. 그리고 케이크 한 개요.직원: 네. 만 이천 원이에요.Alex: 네? 다시 말해 주세요.직원: 만 이천 원이요. 12,000원.Alex: 아, 네. 여기요.직원: 감사합니다. 몇 시에 닫아요? 아, 저희는 아홉 시에 닫아요.Alex: 아홉 시요? 알겠어요. 감사합니다!
★ Both systems, four times, in ten lines. 두 명 · 두 잔 · 한 개 · 아홉 시 are all native; 만 이천 원 is Sino. And Alex uses 다시 말해 주세요 the moment the price goes past — which is exactly right, because prices are where you will lose the thread.

8. Exercises

A. Sino — write it in Hangul.

  1. 3 2. 7 3. 15 4. 48 5. 100 6. 2026

B. ⚠️ Group by 만.

  1. 10,000 2. 50,000 3. 1,000,000 4. 15,000

C. Native — write it in Hangul.

  1. 1 2. 4 3. 8 4. 12 5. 20 6. 25

D. ★ Sino or native?

  1. 5,000 won 2. 3 o'clock 3. 30 minutes 4. 25 years old
  2. 2 people 6. the year 2026 7. 4 apples 8. 3rd floor

E. ★ Change the number before the counter.

  1. 하나 + 개 2. 둘 + 잔 3. 셋 + 명 4. 넷 + 살 5. 스물 + 살

F. Order it.

  1. Two coffees, please. 2. Three beers, please. 3. One cake, please.
  2. Two people. 5. How much is it?

G. ⚠️ Fix the mistake.

  1. 커피 이 잔 주세요.
  2. 스물 살이에요.
  3. 삼 시 삼십 분이에요.
  4. 두 개 커피 주세요.
  5. 손님 두 명 오셨어요. (politely)
Answers

A. 1. 삼 2. 칠 3. 십오 4. 사십팔 5. 백 6. 이천이십육 B. 1. 2. 오만 3. ★ 백만 4. 만 오천 C. 1. 하나 2. 넷 3. 여덟 4. 열둘 5. 스물 6. 스물다섯 D. 1. Sino 2. native 3. Sino 4. native 5. native 6. Sino 7. native 8. Sino E. 1. 개 2. 잔 3. 명 4. 살 5. 스무F. 1. 커피 두 잔 주세요. 2. 맥주 세 병 주세요. 3. 케이크 한 개 주세요. 4. 두 명이요. 5. 얼마예요? G. 1. 두 잔 (counting things = native) 2. 스무 살 3. 세 시 삼십 분 (hour = native) 4. 커피 두 개 — noun first 5. 두 분 (guests take 분)

9. Today's 10 sentences (flashcards)

  1. 얼마예요? — How much is it?
  2. 만 오천 원이에요. — It's 15,000 won
  3. 너무 비싸요. — That's too expensive
  4. 커피 두 잔 주세요. — Two coffees, please
  5. 맥주 한 병 주세요. — One beer, please
  6. 몇 분이세요? — How many people? (what staff ask)
  7. 두 명이요. — Two people
  8. 스물다섯 살이에요. — I'm 25
  9. 세 시 삼십 분이에요. — It's 3:30
  10. 다시 말해 주세요. — Please say that again

10. 📲 Upload to LangNote

Upload section 3 (which system when), section 5 (the counters) and section 9 → study language Korean.

MissionWhat to do with it today
🎧 PodcastCount 1–20 in both systems, out loud, with it. Boring and the only thing that works
✍️ DictationToday's key mission. Prices are where your ear will fail — 만 vs 백만
🗣 Shadowing세 시 삼십 분, ten times. Then 한 개 두 개 세 개 네 개
📖 VocabCounters as whole phrases — 커피 두 잔, 두 명, 스무 살
❓ QuizSino vs native, and the five changing numbers
Count real things out loud tonight. Objects on your desk with , people in a photo with , cups in your kitchen with . Twenty items, three minutes — and it drills the counter, the number change and the word order at once.
Tomorrow: time and dates, where both systems meet every single day.

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