Verbseoul.
하다 verb (adj)
위대하다widaehadagreat

To say great politely in the present tense, use 위대해요 (wee-dae-hae-yoh). Below is the full conjugation of 위대하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
위대해
wee-dae-hae
위대해요
wee-dae-hae-yoh
위대합니다
wee-dae-hahm-nee-dah
Past
위대했어
wee-dae-hae-ssuh
위대했어요
wee-dae-hae-ssuh-yoh
위대했습니다
wee-dae-hae-sseum-nee-dah
Future
위대할 거야
wee-dae-hahl- -guh-yah
위대할 거예요
wee-dae-hahl- -guh-yae-yoh
위대할 겁니다
wee-dae-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
위대하세요
wee-dae-hah-sae-yoh
Suggestion / Let's Polite (요)
위대해요
wee-dae-hae-yoh
Question Polite (요)
위대해요?
wee-dae-hae-yoh-?
Connective “and” — (고)
위대하고
wee-dae-hah-goh
Conditional “if” — (면)
위대하면
wee-dae-hah-myuhn
Noun form — (기)
위대함
wee-dae-hahm