Verbseoul.
하다 verb (adj)
영원하다yeongwonhadaeternal, permanent, everlasting

To say eternal, permanent, everlasting politely in the present tense, use 영원해요 (yuhng-wuhn-hae-yoh). Below is the full conjugation of 영원하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
영원해
yuhng-wuhn-hae
영원해요
yuhng-wuhn-hae-yoh
영원합니다
yuhng-wuhn-hahm-nee-dah
Past
영원했어
yuhng-wuhn-hae-ssuh
영원했어요
yuhng-wuhn-hae-ssuh-yoh
영원했습니다
yuhng-wuhn-hae-sseum-nee-dah
Future
영원할 거야
yuhng-wuhn-hahl- -guh-yah
영원할 거예요
yuhng-wuhn-hahl- -guh-yae-yoh
영원할 겁니다
yuhng-wuhn-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
영원하세요
yuhng-wuhn-hah-sae-yoh
Suggestion / Let's Polite (요)
영원해요
yuhng-wuhn-hae-yoh
Question Polite (요)
영원해요?
yuhng-wuhn-hae-yoh-?
Connective “and” — (고)
영원하고
yuhng-wuhn-hah-goh
Conditional “if” — (면)
영원하면
yuhng-wuhn-hah-myuhn
Noun form — (기)
영원함
yuhng-wuhn-hahm