Verbseoul.
하다 verb (adj)
주요하다juyohadato be main

To say to be main politely in the present tense, use 주요해요 (choo-yoh-hae-yoh). Below is the full conjugation of 주요하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
주요해
choo-yoh-hae
주요해요
choo-yoh-hae-yoh
주요합니다
choo-yoh-hahm-nee-dah
Past
주요했어
choo-yoh-hae-ssuh
주요했어요
choo-yoh-hae-ssuh-yoh
주요했습니다
choo-yoh-hae-sseum-nee-dah
Future
주요할 거야
choo-yoh-hahl- -guh-yah
주요할 거예요
choo-yoh-hahl- -guh-yae-yoh
주요할 겁니다
choo-yoh-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
주요하세요
choo-yoh-hah-sae-yoh
Suggestion / Let's Polite (요)
주요해요
choo-yoh-hae-yoh
Question Polite (요)
주요해요?
choo-yoh-hae-yoh-?
Connective “and” — (고)
주요하고
choo-yoh-hah-goh
Conditional “if” — (면)
주요하면
choo-yoh-hah-myuhn
Noun form — (기)
주요함
choo-yoh-hahm