Korean grammar, step by step

The -아요/-어요 ending marks polite speech. It is the same for all persons — Korean verb forms do not agree with who is doing the action, only with formality level. -아요 follows bright vowels (ㅏ/ㅗ); -어요 follows all others.

Korean is Subject–Object–Verb: the verb always comes at the very end of the clause. Every other element — objects, time words, location phrases — must appear before it.

은/는 (topic marker) frames what the sentence is about — typically known or contrasted information. 이/가 (subject marker) highlights new information or puts focus on who performs the action. Both follow vowel and consonant stems differently.

을/를 marks the direct object. 을 attaches after a consonant-final syllable; 를 attaches after a vowel-final syllable. The particle, not word order, tells you what is being acted on.

에 marks a destination (going to) or location of existence (being at). 에서 marks the location where an action takes place. The same place takes a different particle depending on whether you are moving there, being there, or doing something there.

Past tense is formed by inserting -았- (after ㅏ/ㅗ vowel stems) or -었- (all others) before the polite -어요 ending. The same ending is used for all persons — no agreement by person or gender.

-(으)ㄹ 거예요 expresses future plans or predictions. The modifier ending -(으)ㄹ attaches to the verb stem (ㄹ after vowel stems; 을 after consonant stems), followed by the noun 거 (thing/fact) and the copula 예요. It literally means "it will be the case of doing."

Korean has three negation forms: 안 before the verb (short, general), -지 않아요 after the stem (slightly more emphatic), and 못 before the verb (inability). 없다 (to not exist / not have) is the negative counterpart of 있다.

Korean adjectives are stative verbs — they conjugate for tense and politeness just like action verbs, and they serve as predicates on their own without a separate "to be." The copula 이다 (to be) links nouns to their identity; 아니다 is its negative.

의 (ui) marks possession and corresponds to English "'s" or "of." In casual speech it is frequently omitted — context and word order make the relationship clear. Nouns can also stack directly into compounds without any particle.

-고 있어요 marks a progressive action: the connective -고 links the verb stem to 있어요 (to exist/be), literally "existing in the state of doing." The same pattern forms past progressives with -고 있었어요.

-고 lists or sequences actions ("and then"). -(아/어)서 expresses cause or a method ("because" / "by doing") and cannot appear in the past tense. -(으)면 introduces a condition ("if").

Korean threads politeness into every verb form. 해요체 (polite informal) is used in most everyday situations. 합쇼체 (formal) appears in presentations and formal writing. 반말 (plain/informal) is used with close friends or children. Pronouns also shift: 저 (humble "I") in polite speech, 나 (plain "I") in informal.

Ability uses -(으)ㄹ 수 있어요 ("there is a way to do"), negated with -(으)ㄹ 수 없어요. Desire uses -고 싶어요 ("want to do"). To suggest trying something, -아/어 보다 is used ("do and see").

Korean relative clauses precede the noun they modify. A modifier ending replaces the final verb: -(으)ㄴ for completed/past actions, -는 for present ongoing actions, and -(으)ㄹ for future or potential actions. The noun immediately follows the modifier ending.

Korean grammar is particles, verb-final order, and speech level working together as a system. Once you can see particles marking roles, modifier endings building clauses, and the polite ending closing every verb, you can decode and build complex sentences.