[ADJ-GRADED 能被表示程度的副词或介词词组修饰的形容词]无法辩解的;不可原谅的;不可宽恕的 If you say that something is inexcusable, you are emphasizing that it cannot be justified or tolerated because it is extremely bad.
[emphasis]
He said the killing of innocent people was inexcusable...
他说滥杀无辜是不可原谅的。
The Home Office has been accused of inexcusable incompetence.
内政部被指责能力极其低下。
inexcusably
She had been inexcusably careless.
她太粗心大意了。
Oxford
in·ex·cus·able/ˌɪnɪkˈskjuːzəbl; NAmEˌɪnɪkˈskjuːzəbl/adjectivetoo bad to accept or forgive 不可宽恕的;无法原谅的SYN