Heptaoxacycloheneicosane
[化] 七氧代环二十一烷; 21-冠-7; 21-冠醚-7
🗣️ 情景例句
There aren't window seats left, but a few enter seats are open.
那些靠窗的位子已没有了，但里面的位子还有。
I'm going to send her six bags.
我要送给她六袋。
Of course, sometimes we're together too often, and we fight.
当然，有时候我们在一起太多而打起架来。