【题目】改错：what is he do? She listening to music. __________________
【答案】What is he doing? He is listening to music.
【解析】
句意：—他在干什么？—他在听音乐。句首首字母要大写，what改为What；现在进行时的构成为：主语+be动词+现在分词，do要改为doing；问句中主语是he，答语要用相同的主语，所以She要改为he；答语中缺少be动词，因主语是he，所以be动词用is。故答案为What is he doing? He is listening to music.