She had learned some English before she came to the institute. 她在来学院之前已学过一些英语。 He said that he had been abroad for 3 years. 他说他在国外待了3年了。 2.表示从过去某一时间开始,一直延续到过去的另一时间的动作,常用的时间状语有:by then,by that time,until,by the end of,before 2011,by the time+句子等。