Verbseoul.
하다 verb
수사하다susahadato investigate

To say to investigate politely in the present tense, use 수사해요 (soo-sah-hae-yoh). Below is the full conjugation of 수사하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
수사해
soo-sah-hae
수사해요
soo-sah-hae-yoh
수사합니다
soo-sah-hahm-nee-dah
Past
수사했어
soo-sah-hae-ssuh
수사했어요
soo-sah-hae-ssuh-yoh
수사했습니다
soo-sah-hae-sseum-nee-dah
Future
수사할 거야
soo-sah-hahl- -guh-yah
수사할 거예요
soo-sah-hahl- -guh-yae-yoh
수사할 겁니다
soo-sah-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
수사하세요
soo-sah-hah-sae-yoh
Suggestion / Let's Polite (요)
수사해요
soo-sah-hae-yoh
Question Polite (요)
수사해요?
soo-sah-hae-yoh-?
Connective “and” — (고)
수사하고
soo-sah-hah-goh
Conditional “if” — (면)
수사하면
soo-sah-hah-myuhn
Noun form — (기)
수사함
soo-sah-hahm