clueless

1. ADJ If you describe someone as clueless, you are showing your disapproval of the fact that they do not know anything about a particular subject or that they are incapable of doing a particular thing properly. 無(wú)知的[非正式] [oft ADJ 'about' n]

I came into adult life clueless about a lot of things that most people take for granted. 我成年后，發(fā)現(xiàn)自己對(duì)大多數(shù)人認(rèn)為是理所當(dāng)然之事知之甚少。