Fill each gap with one suitable word to complete the conversation.
Nam: Phong, I learned an interesting word from school today, ‘megacity'.
Phong: ‘Megacity', like in the ‘megabyte' or ‘megadeath'?
Nam: Right. A is a very large city with a big population.
Phong: Is our city a megacity?
Nam: No, I think it's too to be called ‘megacity'.
Phong: Can you name some?
Nam: My teacher named some. are Manila, Tokyo, London …
Phong: And New York, and Shanghai, and …
Nam: How do you know them?
Phong: I read about the cities in the world. But I don't know they are called megacities.