have/know all the answersinformal to be very sure that you know everything about a situation, especially when you do not 〔自以为〕无所不知，通晓一切 He acts like he has all the answers. 他一副无所不知的样子。
have/know all the answers• He was a modest and unassuming man who never gave the impression that he knew all the answers.• In the current situation many issues as yet remain unresolved and we do not have all the answers.• But I don't have all the answers.• Will that have all the answers?• Anyone can claim to have all the answers.• We are supposed to have all the answers.
→ have/know all the answers at answer1(1)