Verbseoul.
ㅂ irregular (adj)
두껍다dukkeopdato be thick

To say to be thick politely in the present tense, use 두꺼워요 (doo-gguh-wuh-yoh). Below is the full conjugation of 두껍다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
두꺼워
doo-gguh-wuh
두꺼워요
doo-gguh-wuh-yoh
두껍습니다
doo-gguhp-sseum-nee-dah
Past
두꺼웠어
doo-gguh-wuh-ssuh
두꺼웠어요
doo-gguh-wuh-ssuh-yoh
두꺼웠습니다
doo-gguh-wuh-sseum-nee-dah
Future
두꺼울 거야
doo-gguh-ool- -guh-yah
두꺼울 거예요
doo-gguh-ool- -guh-yae-yoh
두꺼울 겁니다
doo-gguh-ool- -guhm-nee-dah

Other useful forms

Command Polite (세요)
두꺼우세요
doo-gguh-oo-sae-yoh
Suggestion / Let's Polite (요)
두꺼워요
doo-gguh-wuh-yoh
Question Polite (요)
두꺼워요?
doo-gguh-wuh-yoh-?
Connective “and” — (고)
두껍고
doo-gguhp-goh
Conditional “if” — (면)
두꺼우면
doo-gguh-oo-myuhn
Noun form — (기)
두꺼움
doo-gguh-oom