Polyketone
聚酮
🗣️ 情景例句
Coffee, please.
请来点咖啡。
Children enter school at the age of five,don't they?
孩子们在5岁时入学吗？
As Fred was going in the same direction, he walked along with the tourist.
因为游客与弗雷德走的是同一个方向，他便与游客一道同行。