Question

مچ کسی رو گرفتن
 

Answer 1

catch someone red-handed and catch someone flat-footed

Tom was stealing the car when the police drove by and caught him red-handed

Comments

All right, Also

catch someone with pants down

Answer 2

catch sb in the act of doing sth

Answer 3

GOTCHA

- weren't you at home the night of accident you said? gotcha

Comments

Be onto someone

I'm onto you مچتو گرفتم!