在希腊的一个拘留中心 一名官员用电视给囚犯上课

channel – n. a television or radio station

certificates – n. a document that is official proof that you have finished school or a course of training

insurmountable – adj. impossible to solve or get control of

studio – n. a place where radio or television programs are broadcast

diploma –n. a document which shows that a person has completed a course of study or has graduated from a school

replace – v. to be used instead of (something) else