智慧职教: Match these terms with their Chinese translations（匹配）. gear train driver gear driven gear spur gear gear ratio compound gear train idler gear

"The boy was a couch potato." in the paragraph 4 means_________________. A: the boy was a kind of potato B: the boy liked eating potatoes C: the boy liked eating potatoes on a couch D: the boy was an idler who spends much time on a couch