He did not seem a whit concerned.是什么意思？

He did not seem a whit concerned.

他看来毫不在乎.

he

pron. 他，它，一个人；n. 雄性动物；

例句
Logic had prevailed and he had abandoned the idea.
最终理智占了上风，他打消了那个念头。

did

v. 做( do的过去式)，干，学习，研究；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

not

adv. 不，[用以表示否定、否认、拒绝、禁止等]不是，几乎不，未必，没有[用于否定后面的词或短语]；

例句
It became very clear that the incident was not just an aberration, it was not just a single incident.
事实已经很清楚，这件事不是偶发的，它并不是一起孤立的事件。

seem

v. 好像，仿佛，似乎，装作，看来好像；

例句
We are scared to abandon ourselves to our feelings in case we seem weak or out of control.
我们不敢放纵自己的情感，以免显得太过软弱或缺乏自制。

whit

n. 极少的量，一点儿，丝毫不，一点也不；

例句
He cared not a whit for the social, political or moral aspects of literature...
他毫不在乎文学的社会、政治或道德层面。

concerned

adj. 有关（方面），被牵连的，担心的，烦恼的，关心政治的，关心社会的；vt. 涉及，关心，参与，卷入，使担忧；vi. 有关，利害关系，顾虑，装置；

例句
While economists are free to theorise, company chairmen are concerned with actualities.
经济学家们可自由创建理论，公司总裁们则关心现实情况。