Vinylene
1,2-亚乙烯基, 乙烯撑, 次亚乙烯基
🗣️ 情景例句
See, it works!
瞧， 真有效！
Let difficulties occur but not the loss of courage.
纵使困难重重，也不丧失勇气。
Here and here. And I can only move my arm as much as this.
这儿和这儿。我只能这样摆动手臂。