( He )is a student.( His )sister is a student too. 或： ( She )is a student.( Her )sister is a student too. 祝你学习进步，更上一层楼！ (*^__^*) 不明白的再问哟，请及时采纳，多谢！
HeHis 学习是一件愉快的事！ (*^__^*) 请及时采纳，多谢！
