Verbseoul.
하다 verb
대신하다daesinhadato replace, to substitute

To say to replace, to substitute politely in the present tense, use 대신해요 (dae-sheen-hae-yoh). Below is the full conjugation of 대신하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
대신해
dae-sheen-hae
대신해요
dae-sheen-hae-yoh
대신합니다
dae-sheen-hahm-nee-dah
Past
대신했어
dae-sheen-hae-ssuh
대신했어요
dae-sheen-hae-ssuh-yoh
대신했습니다
dae-sheen-hae-sseum-nee-dah
Future
대신할 거야
dae-sheen-hahl- -guh-yah
대신할 거예요
dae-sheen-hahl- -guh-yae-yoh
대신할 겁니다
dae-sheen-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
대신하세요
dae-sheen-hah-sae-yoh
Suggestion / Let's Polite (요)
대신해요
dae-sheen-hae-yoh
Question Polite (요)
대신해요?
dae-sheen-hae-yoh-?
Connective “and” — (고)
대신하고
dae-sheen-hah-goh
Conditional “if” — (면)
대신하면
dae-sheen-hah-myuhn
Noun form — (기)
대신함
dae-sheen-hahm