Verbseoul.
하다 verb (adj)
철저하다cheoljeohadathoroughgoing, thorough, exhaustive

To say thoroughgoing, thorough, exhaustive politely in the present tense, use 철저해요 (chuhl-chuh-hae-yoh). Below is the full conjugation of 철저하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
철저해
chuhl-chuh-hae
철저해요
chuhl-chuh-hae-yoh
철저합니다
chuhl-chuh-hahm-nee-dah
Past
철저했어
chuhl-chuh-hae-ssuh
철저했어요
chuhl-chuh-hae-ssuh-yoh
철저했습니다
chuhl-chuh-hae-sseum-nee-dah
Future
철저할 거야
chuhl-chuh-hahl- -guh-yah
철저할 거예요
chuhl-chuh-hahl- -guh-yae-yoh
철저할 겁니다
chuhl-chuh-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
철저하세요
chuhl-chuh-hah-sae-yoh
Suggestion / Let's Polite (요)
철저해요
chuhl-chuh-hae-yoh
Question Polite (요)
철저해요?
chuhl-chuh-hae-yoh-?
Connective “and” — (고)
철저하고
chuhl-chuh-hah-goh
Conditional “if” — (면)
철저하면
chuhl-chuh-hah-myuhn
Noun form — (기)
철저함
chuhl-chuh-hahm