One of the first pleasant surprises in Korean is that 책 can mean a book, the book, books, or the books, and nobody is confused.
The second surprise, a few weeks later, is realising you have no idea how Koreans keep track.
What Korean does not have
No articles. No equivalent of a, an, or the.
No obligatory plural. 책 covers one book or many. There is a plural marker 들, but it is optional and used far less than English speakers expect.
No verb agreement. 가요 works for I, you, he, she, we, and they. The verb does not change.
No grammatical gender. Nothing to memorise.
The result is that a Korean sentence often carries less explicit information than its English translation, and relies on context to fill the gap.
So how do you say "the"?
Usually you do not. If it is obvious which one you mean, the bare noun is enough.
책 읽었어요. — I read the book. / I read a book.
When it genuinely matters, Korean has other tools.
Demonstratives
- 이 책 — this book
- 그 책 — that book (the one we were talking about)
- 저 책 — that book over there
그 is the closest thing Korean has to a definite article, and it does get used that way when referring back to something mentioned earlier.
Particles
As covered in the article on 은/는 vs 이/가, first mentions take 이/가 and later mentions take 은/는 — which is functionally close to the a → the switch in English.
남자가 왔어요. 그 남자는 키가 컸어요. A man came. The man was tall.
The mistake English speakers make
Because 그 translates as "that," learners start inserting it wherever English would use "the."
✗ 그 커피를 마셨어요.
This sounds like I drank that specific coffee we were discussing — which is odd if nobody discussed any coffee. The natural sentence is just 커피를 마셨어요.
Use 그 only when you are genuinely pointing back at something already established.
About 들
들 marks plural, but it is optional and mostly used for people and definite groups.
학생들이 왔어요. — The students came. 사과 샀어요. — I bought apples. (들 unnecessary)
Adding 들 to everything is another common learner tell. If the number is clear from context or from a number word, leave it off.
With a number, 들 is wrong:
✗ 사과 세 개들 ✓ 사과 세 개
Korean drops whatever is inferable
The article situation is one example of a much broader habit. Korean omits anything the listener can reconstruct.
Subjects disappear.
어디 가요? — Where are you going? 밥 먹으러 가요. — I'm going to eat.
No "you," no "I." Both are obvious.
Objects disappear.
봤어요? — Did you see it? 네, 봤어요. — Yes, I saw it.
Whole clauses disappear in answers, leaving only the new information.
This is the actual adjustment. English requires a full sentence skeleton even when every part is obvious. Korean requires only the part that carries news.
Learners who translate from English produce sentences that are grammatical but strangely complete, with every pronoun spelled out. Native speakers notice.
How to build the habit
Watch what gets left out. When you read a Korean line and its English translation side by side, the English almost always has more words — those extra words are what Korean assumed you already knew.
After a while you start assuming them too, and your sentences get shorter.
K-PATTO shows every line with its English translation for exactly this reason. The gap between the two is where this habit lives. The first ten episodes are free at K-PATTO.