Coboundary operator
[计] 边缘算子
🧩 词语组成解析
[计] 上边缘
🗣️ 情景例句
When I came here,
当我初到这，
A wonder lasts but nine days.
新鲜事儿不久长。
Some of them are going to the park.
他们中有几个正走进公园。