How to Conjugate 공부하다 (to study): regular-하다 Pattern
하다 verbs: 하 + 여요 → 해요. All 하다 verbs follow the same pattern.
Category: Verb Conjugation
The Rule
공부하다 (gongbuhada) means "study" and is a regular Korean verb. To conjugate it, remove 다 from the dictionary form to get the stem 공부하. The stem's last vowel is a bright vowel, so it pairs with 아-type endings. 하다 verbs are the largest category in Korean. 하 + 여요 contracts to 해요. This single pattern covers hundreds of Sino-Korean verbs. Regular verbs like 공부하다 follow predictable patterns, which means once you learn how to conjugate this verb, you can apply the same rules to many other verbs that share similar stem characteristics. The key to Korean conjugation is a two-step analysis: first determine whether the stem's last vowel is bright (ㅏ or ㅗ) or dark (all others), then check whether the stem ends in a vowel or consonant. This determines which set of endings to use and whether contraction or buffer vowels are needed. 공부하다 is an excellent verb to practice because it appears frequently in everyday Korean conversation.
Why English Speakers Struggle
English speakers learning Korean often find verb conjugation overwhelming because English barely changes verb forms. In Korean, every verb ending carries information about tense, politeness, mood, and sometimes the speaker's relationship to the listener. With 공부하다, the main challenge is remembering the correct ending for each situation. The contraction 하 + 여 → 해 is unique to 하다 verbs. English speakers sometimes produce 하여요 which is technically correct but archaic. Modern spoken Korean always uses 해요. Another common difficulty is the concept of speech levels. Korean has at least six distinct politeness levels, though most learners focus on two: 해요체 (polite informal) and 합쇼체 (formal). Using the wrong level can sound disrespectful or awkwardly formal. English has nothing comparable — you would not change the verb form when speaking to your boss versus your friend. Understanding that Korean verb endings are social signals, not just grammar, helps learners appreciate why accuracy matters. Practice 공부하다 in both polite and formal registers until switching between them feels natural.
Present Tense Conjugation
The polite present tense (해요체) of 공부하다 is 공부해요 (gongbuhaeyo). To form this, take the stem 공부하 and add 아요. Since the stem ends in a vowel, contraction may occur depending on the specific vowels involved. The formal present tense (합쇼체) is 공부합니다 (gongbuhamnida). For vowel-ending stems, attach ㅂ니다 by adding ㅂ as a batchim to the stem syllable. The casual present drops 요: just use the stem plus 아. In daily conversation, the polite present covers both ongoing actions and habitual ones. Context and time expressions clarify which meaning is intended. For example, adding 지금 (now) indicates current action, while 매일 (every day) indicates habit. Practice saying sentences with time markers to build natural Korean rhythm.
Past Tense Conjugation
The polite past tense of 공부하다 is 공부했어요 (gongbuhaesseoyo). The past tense marker is 았 for bright-vowel stems. When the stem ends in a vowel, the past marker merges with it. The formal past tense adds 습니다 to the past stem. Korean past tense works somewhat differently from English. It can express completed actions (I ate), experienced states (I was tired), and even discoveries (Oh, it was here!). The past tense in Korean is definitive — it states that something happened. For recent past actions, Koreans often add 방금 (just now) or 아까 (earlier). For distant past, 예전에 (long ago) or 어렸을 때 (when young) provide temporal context. Practice narrating past events using 공부하다 to build fluency with past tense construction. Try describing what you did yesterday using multiple past tense sentences connected with 고 (and then).
Future Tense and Intention
The future tense of 공부하다 uses ㄹ 거예요: 공부할 거예요 (gongbuhal geoyeyo). Since the stem ends in a vowel, ㄹ attaches directly as a batchim. Korean has three main ways to express future meaning, each with different nuances. The ㄹ 거예요 form is the most neutral and common, expressing planned or predicted future actions. The ㄹ게요 form expresses a first-person decision or promise made in the moment. The 겠 form expresses strong intention or conjecture about others. For beginners, focus on ㄹ 거예요 as it covers most situations. When making plans with friends, use this form: 내일 뭐 할 거예요? (What will you do tomorrow?). When someone asks you to do something and you agree on the spot, switch to ㄹ게요 to show your immediate commitment. As you advance, the 겠 form will become important for formal speech and expressing guesses about others' actions.
Negative Forms
The short negation of 공부하다 is 안 공부해요 (an gongbuhaeyo), placing 안 before the verb. The long negation follows the pattern stem + 지 않다. Both mean the same thing, but the long form is slightly more emphatic and preferred in writing. For inability, use 못 before the verb. The distinction between 안 (choice) and 못 (inability) is important in Korean. Saying 안 했어요 means you chose not to do it, while 못 했어요 means circumstances prevented you. This distinction does not exist in simple English negation. Korean also has the negative command form: verb stem + 지 마세요 means "please don't." For example, adding 지 마세요 to the stem creates a polite prohibition. The casual negative command drops 세요, becoming 지 마. Practice all negative forms because they appear in conversation just as often as positive forms. Korean speakers frequently use double negatives for emphasis, which is grammatically correct in Korean unlike in English.
The Power of 하다 Verbs
하다 verbs are perhaps the most important pattern in Korean. By adding 하다 to a noun, you create a verb. 공부 (study as a noun) + 하다 = 공부하다 (to study). This pattern applies to hundreds of words: 운동하다 (to exercise), 요리하다 (to cook), 일하다 (to work), 여행하다 (to travel), 사랑하다 (to love), 전화하다 (to call). All of these conjugate identically to 공부하다. Learn this one pattern and you unlock hundreds of verbs instantly. The noun part can also separate from 하다 with particles inserted between: 공부를 하다, 공부도 하다, 공부만 하다. This flexibility does not change the conjugation — 하다 still conjugates as 해요, 했어요, 할 거예요 regardless of what comes before it. Many 하다 verbs come from Chinese-origin words (한자어), so if you learn some basic Chinese characters, you can guess the meaning of new 하다 verbs. This is a powerful vocabulary expansion strategy unique to Korean and other East Asian languages.
Connecting and Modifier Forms
Korean sentences often chain multiple clauses using connecting verb forms. The most common connector 고 attaches directly to the stem: 공부하고 means "study and." The sequential or causal connector 아서 creates a flow of events or cause-and-effect. The conditional 면 means "if." Modifier forms turn verbs into adjectives that describe nouns. The present modifier 는 attaches to the stem (with consonant adjustments as needed). The past modifier ㄴ/은 and future modifier ㄹ/을 follow the vowel or consonant stem rules. These modifier forms are essential for building complex, natural Korean sentences. Without them, you are limited to simple subject-verb-object patterns. Practice by creating noun phrases: the thing you study, the person who studys, the place where you will study. These structures appear in nearly every Korean conversation.
Practice Strategy
Start with the three core polite forms: 공부해요 (present), 공부했어요 (past), 공부할 거예요 (future). Practice by creating sentences about your daily life using 공부하다. Once these feel natural, add the formal versions for workplace and official situations. Then master the negative forms: 안 공부해요 (don't) and 못 + verb (cannot). A useful exercise is to conjugate 공부하다 through all forms in a single practice session: present, past, future, negative, conditional, connecting, and modifier forms. Write each form down, say it aloud, and create a sentence using it. Compare 공부하다 with other verbs you have learned to reinforce the pattern. If the stem characteristics match (same vowel type, same ending type), the conjugation will be identical. This pattern recognition approach is far more efficient than memorizing each verb's conjugations individually.
공부하다 summary: 공부해요 (present) → 공부했어요 (past) → 공부할 거예요 (future) → 안 공부해요 (negative)
Examples
공부해요 — gongbuhaeyo — study (polite present)
공부했어요 — gongbuhaesseoyo — study (past)
공부할 거예요 — gongbuhal geoyeyo — will study
공부합니다 — gongbuhamnida — study (formal)
안 공부해요 — an gongbuhaeyo — don't study
공부해요 — gongbuhaeyo — study (polite)
열심히 공부해요 — yeolsimhi gongbuhaeyo — study hard
공부하고 있어요 — gongbuhago isseoyo — am studying
Common Mistakes
Incorrect: 공부하어요 → Correct: 공부해요. The stem vowel is bright, so use 아-type endings.
Incorrect: 공부하여요 → Correct: 공부해요. 하여요 is archaic/literary. Modern Korean contracts to 해요.
Incorrect: 공부 안 해요 → Correct: 공부 안 해요 or 안 공부해요. For 하다 verbs, 안 can go before 하다 or before the whole word. Both are acceptable.
Incorrect: 공부하면서 놀아요 → Correct: Grammatically correct but semantically contradictory. While studying and playing is logically contradictory. Use 공부하거나 놀아요 (study or play) instead.
Incorrect: 공부하을 거예요 → Correct: 공부할 거예요. Vowel-ending stem uses ㄹ not 을: 하 + ㄹ = 할.
Quiz
What is the polite present form of 공부하다?
Polite present (해요체) of 공부하다 is 공부해요.
How do you say 'will study' in polite Korean?
Future tense uses ㄹ 거예요: 공부할 거예요.
What makes 공부하다 a 하다 verb?
하다 verbs combine a noun with 하다, creating verb meaning 'to do [noun]'.