inexcusable

Leaving a child unattended in a hot car is an inexcusable act of negligence.

(Chinese) 把孩子单独留在闷热的车里是不可原谅的疏忽行为。

The huge spelling error on the company's front page was considered inexcusable by the manager.

(Chinese) 公司首页上的巨大拼写错误被经理认为是不可原谅的。