Verbseoul.
descriptive
느닷없다neudateopdato be sudden, to be unforeseen

To say to be sudden, to be unforeseen politely in the present tense, use 느닷없어요 (neu-dah-suhp-ssuh-yoh). Below is the full conjugation of 느닷없다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
느닷없어
neu-dah-suhp-ssuh
느닷없어요
neu-dah-suhp-ssuh-yoh
느닷없습니다
neu-dah-suhp-seum-nee-dah
Past
느닷없었어
neu-dah-suhp-ssuh-ssuh
느닷없었어요
neu-dah-suhp-ssuh-ssuh-yoh
느닷없었습니다
neu-dah-suhp-ssuh-sseum-nee-dah
Future
느닷없을 거야
neu-dah-suhp-sseul- -guh-yah
느닷없을 거예요
neu-dah-suhp-sseul- -guh-yae-yoh
느닷없을 겁니다
neu-dah-suhp-sseul- -guhm-nee-dah

Other useful forms

Command Polite (세요)
느닷없으세요
neu-dah-suhp-sseu-sae-yoh
Suggestion / Let's Polite (요)
느닷없어요
neu-dah-suhp-ssuh-yoh
Question Polite (요)
느닷없어요?
neu-dah-suhp-ssuh-yoh-?
Connective “and” — (고)
느닷없고
neu-dah-suhp-goh
Conditional “if” — (면)
느닷없으면
neu-dah-suhp-sseu-myuhn
Noun form — (기)
느닷없음
neu-dah-suhp-sseum