Polyacetylen
聚乙炔; 聚乙炔
🗣️ 情景例句
We were both on the tennis team.
我们都是网球队的队员。
It's a beautiful country with scenic mountain areas.
这个国家很美，它有很多景色宜人的山区。
Dear Ling Feng,
亲爱的Ling Feng：