carved in stone
成語所屬單字carve
carved in stone — 慣用語
1. fixed and unable to be changed, especially of rules, plans, or agreements.
1.慣用語
釋義
不可更改的；一成不變的
fixed and unable to be changed, especially of rules, plans, or agreements.
例句
The deadline isn't carved in stone — we can ask for an extension if we need one.
Her decision to move abroad was not carved in stone, so her friends kept hoping she would stay.