Demarcator
n. 划边界的人；立界物
🗣️ 情景例句
He is working on a book about the Vietnam War.
他正在写一本关于越战的书。
We must arrive there on time.
我们必须准时到那儿。
One day she came into his office and happened to put her hands on the door of a locked safe.
一天，维拉走进父亲的办公室，偶然把手放在一个锁着的保险柜的门上，