Verbseoul.
ㅂ irregular (adj)
고맙다gomapdathankful

To say thankful politely in the present tense, use 고마워요 (goh-mah-wuh-yoh). Below is the full conjugation of 고맙다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
고마워
goh-mah-wuh
고마워요
goh-mah-wuh-yoh
고맙습니다
goh-mahp-sseum-nee-dah
Past
고마웠어
goh-mah-wuh-ssuh
고마웠어요
goh-mah-wuh-ssuh-yoh
고마웠습니다
goh-mah-wuh-sseum-nee-dah
Future
고마울 거야
goh-mah-ool- -guh-yah
고마울 거예요
goh-mah-ool- -guh-yae-yoh
고마울 겁니다
goh-mah-ool- -guhm-nee-dah

Other useful forms

Command Polite (세요)
고마우세요
goh-mah-oo-sae-yoh
Suggestion / Let's Polite (요)
고마워요
goh-mah-wuh-yoh
Question Polite (요)
고마워요?
goh-mah-wuh-yoh-?
Connective “and” — (고)
고맙고
goh-mahp-goh
Conditional “if” — (면)
고마우면
goh-mah-oo-myuhn
Noun form — (기)
고마움
goh-mah-oom