IS this your sister?(改为复数句）

IS this your sister?(改为复数句) IS this your sister?(改为复数句） Is this your sister?(改为复数句） Those are Zhang jie is aunts.(改为 This is your sister.改为复数形式 This is his sister改为复数句 This is my sister 改为复数句 Is this your sister的复数句? is this your dress?改为复数句 Is this your duck?(改为复数句) Is this your photo?改为复数句 This is your teacher 改为复数句 1.This is my sister.改为复数句2.That is my friend.改为复数句