step in/ˈstɛp ɪn/第三人称steps in现在进行时stepping in过去式stepped in过去完成时stepped in1介入, 插手get involved, so as to alter or hinder an action, or through force or threat of force同义词： interveneinterfereinterpose2替代, 顶替act as a substitute同义词： deputizedeputisesubstitute