Verbseoul.
하다 verb
쇠하다soehadato wane, to wither, to decline, to ebb away

To say to wane, to wither, to decline, to ebb away politely in the present tense, use 쇠해요 (swae-hae-yoh). Below is the full conjugation of 쇠하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
쇠해
swae-hae
쇠해요
swae-hae-yoh
쇠합니다
swae-hahm-nee-dah
Past
쇠했어
swae-hae-ssuh
쇠했어요
swae-hae-ssuh-yoh
쇠했습니다
swae-hae-sseum-nee-dah
Future
쇠할 거야
swae-hahl- -guh-yah
쇠할 거예요
swae-hahl- -guh-yae-yoh
쇠할 겁니다
swae-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
쇠하세요
swae-hah-sae-yoh
Suggestion / Let's Polite (요)
쇠해요
swae-hae-yoh
Question Polite (요)
쇠해요?
swae-hae-yoh-?
Connective “and” — (고)
쇠하고
swae-hah-goh
Conditional “if” — (면)
쇠하면
swae-hah-myuhn
Noun form — (기)
쇠함
swae-hahm