讲解：
an irresponsible teenager
没有责任感的少年
an irresponsible attitude
不负责任的态度
It would be irresponsible to ignore the situation.
对这一状况不闻不问是不负责任。

label sb / sth (as) sth
(尤指不公正地)把…称为:
He was labelled (as) a traitor by his former colleagues.
他被以前的同事称为叛徒。

assign sb (to sth / as sth)
指定；指派:
They've assigned their best man to the job.
他们指派了最优秀的人担任这项工作。

be gripped by
对…产生强有力的影响:
I was gripped by a feeling of panic.
我惊恐万状。

be marred by
破坏；毁坏；损毁；损害
The game was marred by the behaviour of drunken fans.
喝醉了的球迷行为不轨,把比赛给搅了。