TRUTH›used when you are saying what is the truth of a situation: He didn't actually say anything important.So what actually happened?
SURPRISE›used when you are saying something surprising: She sounds English but she's actually Spanish.Did you actually meet the president?
MISTAKEmainly UK›used when you are disagreeing with someone or saying no to a request: "You didn't tell me." "Actually, I did.""Do you mind if I smoke?" "Actually, I'd rather you didn't."