Verbseoul.
하다 verb (adj)
뚝뚝하다ttukttukhadahard

To say hard politely in the present tense, use 뚝뚝해요 (ttoog-ttoo-kae-yoh). Below is the full conjugation of 뚝뚝하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
뚝뚝해
ttoog-ttoo-kae
뚝뚝해요
ttoog-ttoo-kae-yoh
뚝뚝합니다
ttoog-ttoo-kahm-nee-dah
Past
뚝뚝했어
ttoog-ttoo-kae-ssuh
뚝뚝했어요
ttoog-ttoo-kae-ssuh-yoh
뚝뚝했습니다
ttoog-ttoo-kae-sseum-nee-dah
Future
뚝뚝할 거야
ttoog-ttoo-kahl- -guh-yah
뚝뚝할 거예요
ttoog-ttoo-kahl- -guh-yae-yoh
뚝뚝할 겁니다
ttoog-ttoo-kahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
뚝뚝하세요
ttoog-ttoo-kah-sae-yoh
Suggestion / Let's Polite (요)
뚝뚝해요
ttoog-ttoo-kae-yoh
Question Polite (요)
뚝뚝해요?
ttoog-ttoo-kae-yoh-?
Connective “and” — (고)
뚝뚝하고
ttoog-ttoo-kah-goh
Conditional “if” — (면)
뚝뚝하면
ttoog-ttoo-kah-myuhn
Noun form — (기)
뚝뚝함
ttoog-ttoo-kahm