Verbseoul.
하다 verb (adj)
간사하다gansahadato be deceitful or cunning

To say to be deceitful or cunning politely in the present tense, use 간사해요 (gahn-sah-hae-yoh). Below is the full conjugation of 간사하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
간사해
gahn-sah-hae
간사해요
gahn-sah-hae-yoh
간사합니다
gahn-sah-hahm-nee-dah
Past
간사했어
gahn-sah-hae-ssuh
간사했어요
gahn-sah-hae-ssuh-yoh
간사했습니다
gahn-sah-hae-sseum-nee-dah
Future
간사할 거야
gahn-sah-hahl- -guh-yah
간사할 거예요
gahn-sah-hahl- -guh-yae-yoh
간사할 겁니다
gahn-sah-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
간사하세요
gahn-sah-hah-sae-yoh
Suggestion / Let's Polite (요)
간사해요
gahn-sah-hae-yoh
Question Polite (요)
간사해요?
gahn-sah-hae-yoh-?
Connective “and” — (고)
간사하고
gahn-sah-hah-goh
Conditional “if” — (면)
간사하면
gahn-sah-hah-myuhn
Noun form — (기)
간사함
gahn-sah-hahm