A1
Two number systems
Why Korean has two sets of numbers, which one goes with which counter, and the mixed system used for telling the time.
Korean has two complete sets of numbers. Both are in daily use, and choosing the wrong one is one of the most audible beginner errors.
| native | Sino-Korean | |
|---|---|---|
| 1 | 하나 | 일 |
| 2 | 둘 | 이 |
| 3 | 셋 | 삼 |
| 4 | 넷 | 사 |
| 5 | 다섯 | 오 |
| 10 | 열 | 십 |
Which goes where
Native numbers count things: people, objects, hours, ages. Sino-Korean numbers handle everything measured or numbered: money, minutes, dates, phone numbers, addresses, floors.
사과 세 개 주세요.
Sagwa se gae juseyo.
Three apples, please.
삼천 원이에요.
Samcheon wonieyo.
It’s three thousand won.
Both sentences contain three. They use different words for it.
Native numbers change before a counter
하나, 둘, 셋, 넷 and 스물 lose their final consonant: 한, 두, 세, 네, 스무.
사과 셋 개 주세요.
사과 세 개 주세요.
셋 becomes 세 in front of a counter. The full form is only used when counting aloud or standing alone.
Native numbers stop early
They run out around 99, and in practice above about 20 people reach for Sino-Korean anyway. Age is the exception that keeps native numbers alive at higher values — 서른, 마흔, 쉰.
Telling the time uses both at once
The hour is native, the minute is Sino-Korean. In the same breath.
세 시 삼십 분.
Se si samsip bun.
Half past three.
세 시 is native, 삼십 분 is Sino-Korean. There is no reason for this beyond history, and it has to be memorised as a fixed pattern.