cast-iron
Definition
Made of strong iron; also, something that is dependable or unchangeable.
中文 由坚硬铁制成的；也指可靠的或不可改变的事物。
Example
"She has cast-iron willpower when it comes to sticking to her goals."
Made of strong iron; also, something that is dependable or unchangeable.
中文 由坚硬铁制成的；也指可靠的或不可改变的事物。
"She has cast-iron willpower when it comes to sticking to her goals."