un·ac·count·a·ble
adjective/ˌʌnəˈkaʊntəbl/
/ˌʌnəˈkaʊntəbl/
(formal)- impossible to understand or explain
无法理解的；难以解释的 - There has been an unaccountable increase in cases of the disease.
这种疾病的病例出现了无法解释的增加。 - For some unaccountable reason, the letter never arrived.
不知何故，那封信始终未寄到。
- There has been an unaccountable increase in cases of the disease.
- unaccountable (to somebody/something) not having to explain or give reasons for your actions to anyone
无须解释（或说明）的；不负责的 - Too many government departments are unaccountable to the general public.
有太多的政府部门不对社会大众负责。
- Too many government departments are unaccountable to the general public.