Do you mean to say how are they formed? If so, here is a basic example of a verb conjugated into the present, past, and future tenses. (basic/dictionary form):하다 (present tense):해요 (past tense):했어요 (future tense): 할 거예요 These are the polite spoken forms. You can tell from the "요" at the end. Does this sort of answer your question? Here is a really good website you can look at that should be able to help: http://www.talktomeinkorean.com/curriculum/ :)