A2used to reply completely or to emphasize something and show that there is no doubt about it: She certainly had a friend called Mark, but I don't know whether he was her boyfriend."This is rather a difficult question." "Yes, it's certainly not easy.""Do you think more money should be given to education?" "Certainly!""Had you forgotten about our anniversary?" "Certainly not! I've reserved a table at Michel's restaurant for this evening."CertaintyConfidence and self-assuranceA2used when agreeing or disagreeing strongly to a request: "Could you lend me £10?" "Certainly.""Did you take any money out of my purse?" "Certainly not!"CertaintyConfidence and self-assurance