【题目】When I wanted to show myself up at the party, the song I ________ so many times suddenly became difficult.
A.am practicingB.had practicedC.will be practicingD.have practiced
在线课程【答案】B
【解析】
考查时态。句意：当我想在晚会上展示自己时，我练习过很多遍的那首歌突然变得很难了。practice这一动作发生在became之前，也就是过去的过去，用过去完成时，故B项正确。