용언
From Jonathan Gardner's Korean Notebook
There are two kinds of verbs:
- Action verbs (동사), such as "to eat", "to be eaten", "to feed", etc...
- Adjective verbs (형용사), such as "to be big", "to be small", and generally, "to be (adjective)".
Note that there are adjects as you know them in English, namely, 관형사, but these are a rare curiosity and not the rule. Most adjectives are really verbs.
Both kinds of verbs follow similar rules of "conjugation", or really, agglutinization. Sometimes it's hard to tell the difference between the two if it were not for context.
Koreans love their verbs. You can probably survive Korea knowing only the 500 verbs they use all the time. When I speak Korean, I rarely use any nouns if I can avoid it.