inexcusable
adj. 不可原谅的；没法辩解的；不可宽恕的
例句
He said the killing of innocent people was inexcusable.
他说滥杀无辜是不可原谅的。
《柯林斯英汉双解大词典》
Conditions are good in school. It's inexcusable not to study hard.
学校环境好，不用功念书可说不过去。
《新英汉大辞典》
That would be inexcusable, and entirely self-inflicted by Washington.
这将是不可饶恕的，而这一切都是华盛顿自作自受的结果。
