Learn the job with the number
Korean has two main number systems: Sino-Korean and native Korean. Choosing one depends on what you are counting. Rather than memorizing two long lists without context, learn small number-and-noun combinations you can actually use.
Sino-Korean numbers begin 일, 이, 삼, 사, 오, 육, 칠, 팔, 구, 십. Native Korean numbers begin 하나, 둘, 셋, 넷, 다섯. Both matter, but you can start with a few everyday jobs and expand gradually.
Prices use Sino-Korean numbers
원 is the Korean currency unit. 천 means one thousand and 만 means ten thousand. 삼천 원 is 3,000 won, 오천 원 is 5,000 won, and 만 원 is 10,000 won. A price question such as 이거 얼마예요? means how much is this?
Read a price aloud, then check the written digits. This helps prevent the common confusion between a thousand and ten thousand. Practice several realistic amounts, but always check the actual amount displayed when making a purchase.
Items and drinks use counters
A counter tells you the kind of thing being counted. 개 is a general item counter, 잔 counts cups or glasses of drinks, and 명 counts people. In these combinations, use native Korean numbers. The first four shorten before counters: 하나 → 한, 둘 → 두, 셋 → 세, 넷 → 네.
사과 두 개 means two apples. 커피 한 잔 means one cup of coffee. 두 명 means two people. A restaurant serving is a useful exception: 인분 commonly goes with Sino-Korean numbers, so two servings is 이 인분. Learn the counter together with its number pattern.
A clock uses both systems
Ordinary clock time uses native Korean numbers for hours and Sino-Korean numbers for minutes. 두 시 삼십 분 is 2:30. 오전 marks a.m., and 오후 marks p.m. Add 에 to name the time of an action: 두 시에 만나요 means let’s meet at two.
Practice matching an audio time to a clock face or written digits. Then reverse the exercise and say the Korean time yourself. Remember that identifying the right number system is only one part of listening: you also need to hear the number clearly.