Figuring out how to conjugate verbs is a bit like a coin sorter.
1. VOWEL. What is it’s final vowel? If it is an ‘ㅏ’ or ‘ㅗ’ the clock theory says it goes in the slot to get 아 added when conjugating. Otherwise, it goes down the other slot of verb types that get 어 added.
2. SUB-TYPE. Next, decide which of the three subtypes:
- verbs that end in a vowel
- verbs that end in a consonant
- verbs that end in ~ㄹ
3. CHANGED FORM. Next, decide if the tense you want needs the changed or unchanged form.
4. POLITENESS LEVEL. Next, decide on the politeness level depending on your audience.
I believe honorifics come in next depending on who you are speaking about, but we haven’t gotten that far in Korean Digital Academy yet.
As a computer programmer, I would describe this as a decision tree.