Polystream
多氯苯
🗣️ 情景例句
I grew up in Beijing, but I was in Los Angeles for two years.
我在北京长大，不过在洛杉矶已呆了两年。
Come to see me tomorrow if it is convenient to you.
你如果方便的话，明天来看我。
I like television very much.How much does it cost?
我非常喜欢这台电视机。请问它多少钱？