it was stolen twenty years ago 这句话中,为什么stolen后没有介词

it was stolen twenty years ago 这句话中,为什么stolen后没有介词 It was stolen twenty years ago when Someone _____ it twenty years ago.为什么用stole 而不用has stolen? 1.The bike,____my father bought ten years ago,was stolen yes My car was being_______when it was stolen. he was believed to have stolen it 为什么有was,believed是怎么回事,是什么时 英语语法：He is the man whose car was stolen .这句话whose是什么用法 请帮忙翻译一下这句话：She was found in possession of stolen goods. What was the woman twenty years ago? It was twenty years ago before he returned to which he was b the bicycle was stolen.dan was robbed It is no longer what it was twenty years ago.是什么从句?