Conjugating New Words

Reviewing the Three Rules

Before conjugating a new word, always start by dropping -다 from the dictionary form to find the stem.

Then, look at the ending you want to attach. In Korean, endings follow one of three main rules:

Rule 1: Endings that just attach directly.
Rule 2: Endings that require you to choose between 아 or 어.
Rule 3: Endings that require you to check for a batchim (bottom consonant).

Core takeaway: Drop -다

Reviewing the Three Rules

Before conjugating a new word, always start by dropping -다 from the dictionary form to find the stem.

Then, look at the ending you want to attach. In Korean, endings follow one of three main rules:

Rule 1: Endings that just attach directly.

Rule 2: Endings that require you to choose between 아 or 어 .

Rule 3: Endings that require you to check for a batchim (bottom consonant).

Core takeaway: Drop -다

Rule 1: Endings That Just Attach

Some endings, like -고 (and) and -지만 (but), are very simple. They do not care about the vowels or consonants in the stem.

Just drop -다 and attach the ending directly.

Dictionary Form · -고 · -지만

타다 · 타고 · 타지만

마시다 · 마시고 · 마시지만

닫다 · 닫고 · 닫지만

Core takeaway: -고 and -지만

Rule 2: Choosing 아 or 어

Endings like -아요/-어요 (present) and -았어요/-었어요 (past) require you to check the stem's last vowel.

If the last vowel is ㅏ or ㅗ , choose the 아 form.

For all other vowels, choose the 어 form.

Remember that vowels often blend together, and the vowel ㅡ drops when it meets these endings.

Dictionary Form · Present (-아요/-어요) · Past (-았어요/-었어요)

닫다 (has ㅏ) · 닫아요 · 닫았어요

마시다 · 마셔요 · 마셨어요

바쁘다 (ㅡ drops) · 바빠요 · 바빴어요

Core takeaway: Check last vowel

Reviewing the Three Rules