Polyacetylene
聚乙炔
🗣️ 情景例句
This is she.
我就是。
I'm very pressed for cash at the moment, can I pay you next week?
我现在手头有点紧，再周再付给你行吗？
This is my friend, Ann. Ann, this is Uncle Wang.
这是我的朋友安。安，这是王叔叔。