Retro
n. 制动火箭, 减速火箭；（服装式样等）重新流行
🗣️ 情景例句
No, thanks.
不用了， 谢谢。
Will you please lock the door when you leave?
请您当你离开时，锁门？
What was the population of the less developed countries in 1950?
1950年不太发达国家的人口是多少？