clueless
adj. 很愚蠢的；一无所知的，无能为力的（含贬义）；无线索的；无知的
例句
He's completely clueless about computers.
他对计算机一窍不通。
《牛津词典》
I came into adult life clueless about a lot of things that most people take for granted.
我成年后，发现自己对大多数人认为是理所当然之事知之甚少。
《柯林斯英汉双解大词典》
Some companies now offer etiquette seminars for employees who may be competent professionally but clueless socially.
一些公司现在为那些专业能力强但社交能力差的员工提供礼仪培训。
