Great Quiz! Completely forgot obvious ones such as Seoul and DC. I almost didn’t type in mexico city bc i always write just mexico since most quizzes allow it. Also, since 1982, the absolute mouthful of Sri Jayawardenepura Kotte has been the capital of Sri Lanka, though Colombo is the largest city in the country.
Colombo IS the capital or at least partially. Much like South Africa, Sri Lanka's Government branches are split up between cities so you have the Legislative and Administrative Capital being in Sri Jayawardenepura Kotte while Colombo Serves as the Judicial and Executive Capital.
Usually Mexico for Mexico City, Bagdad for Baghdad for example.