Verbseoul.
하다 verb
예약하다yeyakhadato make a reservation, to book

To say to make a reservation, to book politely in the present tense, use 예약해요 (yae-yah-kae-yoh). Below is the full conjugation of 예약하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
예약해
yae-yah-kae
예약해요
yae-yah-kae-yoh
예약합니다
yae-yah-kahm-nee-dah
Past
예약했어
yae-yah-kae-ssuh
예약했어요
yae-yah-kae-ssuh-yoh
예약했습니다
yae-yah-kae-sseum-nee-dah
Future
예약할 거야
yae-yah-kahl- -guh-yah
예약할 거예요
yae-yah-kahl- -guh-yae-yoh
예약할 겁니다
yae-yah-kahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
예약하세요
yae-yah-kah-sae-yoh
Suggestion / Let's Polite (요)
예약해요
yae-yah-kae-yoh
Question Polite (요)
예약해요?
yae-yah-kae-yoh-?
Connective “and” — (고)
예약하고
yae-yah-kah-goh
Conditional “if” — (면)
예약하면
yae-yah-kah-myuhn
Noun form — (기)
예약함
yae-yah-kahm