Verbseoul.
하다 verb
세수하다sesuhadato wash one's face

To say to wash one's face politely in the present tense, use 세수해요 (sae-soo-hae-yoh). Below is the full conjugation of 세수하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
세수해
sae-soo-hae
세수해요
sae-soo-hae-yoh
세수합니다
sae-soo-hahm-nee-dah
Past
세수했어
sae-soo-hae-ssuh
세수했어요
sae-soo-hae-ssuh-yoh
세수했습니다
sae-soo-hae-sseum-nee-dah
Future
세수할 거야
sae-soo-hahl- -guh-yah
세수할 거예요
sae-soo-hahl- -guh-yae-yoh
세수할 겁니다
sae-soo-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
세수하세요
sae-soo-hah-sae-yoh
Suggestion / Let's Polite (요)
세수해요
sae-soo-hae-yoh
Question Polite (요)
세수해요?
sae-soo-hae-yoh-?
Connective “and” — (고)
세수하고
sae-soo-hah-goh
Conditional “if” — (면)
세수하면
sae-soo-hah-myuhn
Noun form — (기)
세수함
sae-soo-hahm