Polysulfuration
聚硫化作用
🗣️ 情景例句
Tom gave Helen an apple in exchange for a piece of cake.
汤姆用一个苹果和海沦换一块蛋糕。
How many provinces do you have?
你们有多少个区？
Tony speaks English and he plays tennis.
托尼会说英语，打网球。