Comparative Sentences: A는 B보다 (더) …

To say "Seoul is bigger than Busan," English does two things at once: it marks the standard of comparison with the word than, and it reshapes the adjective itself — big becomes bigger. Korean does only the first. It marks the standard with the particle 보다 ("than"), and it leaves the adjective completely unchanged: 크다 stays 크다, never morphing into a "-er" form. The whole comparison rides on the particle, optionally reinforced by the adverb 더 ("more"). Once you stop hunting for a comparative form of the adjective — because there isn't one — Korean comparisons become almost mechanical.

The template: A는 B보다 (더) …

The basic shape is A는 B보다 (더) [predicate]: A is the thing being described, B is the standard it is measured against (with 보다 glued to it), and the predicate states the quality. 더 ("more") usually appears before the predicate, but it is optional — 보다 already implies "more," so the sentence works without it.

Look closely at the adjectives: 커요 (from 크다), 추워요 (from 춥다), 빨라요 (from 빠르다). Every one is just the ordinary predicate form — the same word you would use in a plain non-comparative sentence like 서울은 커요 ("Seoul is big"). Nothing about them signals "more." The comparison lives entirely outside the adjective, in 보다 and 더.

더 is optional; 보다 is not

Because 보다 by itself already means "than (and therefore more)," the 더 is frequently dropped, especially in casual speech. Both versions below are natural and mean the same thing:

The second example shows how flexibly the "standard" slot fills: 생각 ("thought") + 보다 = "than (my) thought," a hugely common Korean idiom for "more/less than expected." You can compare against a noun (버스보다), a pronoun (저것보다), or an abstraction (생각보다) — whatever the "than" phrase would be in English, attach 보다 to it.

To strengthen the comparison, swap 더 for 훨씬 ("much, far"):

"Less" is 덜

Where English piles up "less X," Korean uses the adverb 덜 ("less") in the exact slot 더 would occupy. The adjective still does not change.

Note that Koreans often prefer to flip a 덜 sentence into a positive 더 one — rather than "less expensive," saying 저것이 이것보다 더 비싸요 ("that one is more expensive than this one"). Both are correct; 덜 is perfectly idiomatic, but the positive framing is very common.

Preference: comparing with 좋아하다

A special, high-frequency case is stating a preference — "I like X more than Y." The liked thing takes the object particle 을/를 (because 좋아하다 "to like" is a transitive verb), and the rejected standard takes 보다:

Watch the particle split carefully: the standard (커피, 여름) gets 보다; the preferred thing (차, 겨울) gets 을/를. Beginners frequently cross these wires — see the mistakes below.

Word order is free — the particle carries the meaning

Because 보다 marks the standard no matter where it sits, Korean can scramble the order without ambiguity. All of these mean "Seoul is bigger than Busan," because 부산보다 is unmistakably "than Busan" wherever it lands — this is particle-driven scrambling in action:

The 보다 phrase can lead, follow, or sit in the middle; the meaning is fixed by the particle, not by position. This is why the "A는 B보다" order is a default, not a rule — fronting 부산보다 for emphasis is completely natural.

Superlatives: 제일 / 가장

To go from comparative ("more than one thing") to superlative ("the most of all"), drop 보다 entirely and put 제일 (casual) or 가장 (neutral/formal) before the predicate. The domain of comparison — "out of these," "in Korea" — is usually named with 중에서 or 에서.

제일 and 가장 are interchangeable in meaning; 제일 is a touch more colloquial, 가장 a touch more formal and common in writing. Crucially, a superlative does not use 보다 — it names a whole domain, not a single rival. The full treatment of 제일/가장 lives on the superlative page.

Common Mistakes

1. Dropping 보다 and expecting 더 to mean "than." 더 only means "more"; it cannot mark the standard. Without 보다, there is no "than."

2. Trying to inflect the adjective. There is no comparative form of a Korean adjective — the base predicate does all the work.

3. Attaching 보다 to the thing being described instead of the standard. 보다 always marks the than-noun; putting it on the wrong noun reverses the meaning.

4. Marking a preference's object with 이/가. 좋아하다 ("to like") is transitive, so the preferred thing takes 을/를, not 이/가.

5. Using 더 for a superlative. 더 means "more (than one thing)"; "the most (of all)" is 제일/가장.

Key Takeaways

• The comparative template is A는 B보다 (더) [predicate]: 보다 ("than") marks the standard, 더 ("more") is optional reinforcement.
• Korean adjectives never inflect for comparison — 크다 stays 크다. There is no "-er" ending; the particle and adverb do all the comparing.
• "Less" = 덜, in the same slot as 더 (덜 비싸요).
• Word order is free: 보다 fixes the standard wherever it sits (부산보다 서울이 커요 = 서울은 부산보다 커요).
• Preferences split the particles: standard takes 보다, preferred thing takes 을/를 (커피보다 차를 좋아해요).
• Superlatives drop 보다 and use 제일 (casual) or 가장 (formal), usually with 중에서/에서 for the domain.