They professed complete ignorance of what had happened.他们声称对所发生的事一无所知。We are in complete ignorance of his plans.我们对他的计划一无所知。I am embarrassed by my complete ignorance of history.我对历史一无所知，这让我很难堪。He showed complete ignorance of the most basic historical facts.他对最基本的历史事实显得一无所知。