What does 一事 mean in 美国总统特朗普在被问及前顾问班农被捕一事时表示?
一事 is short for 這一件事 (this thing; this event; this matter)
In your post, '前顾问班农被捕' is the event
&quot;前顾问班农被捕(一事)&quot; = &quot;(the event of) 前顾问班农被捕&quot;
Similarly:
他设法把话题从他离婚一事(這一件事)上引开
他辩称路上人多而把迟到一事(這一件事)推脱得一乾二净
一事 can also be used literally as &quot;one thing&quot; (mostly in classical Chinese)
e.g. 在下有一事相求 - There's one thing that I wanted your help