Prepurging
洗炉, 清炉(清除炉内气体)
🗣️ 情景例句
May I ask who's calling?
请问你是谁？
This week he took his first vacation from work in five years.
五年来，他本周破例第一次休假。
What will be the population of these countries by the end of the twentieth century?
到20世界末较发达国家的人口将是多少？