These are cakes 改为单数形式

These are cakes 改为单数形式 These are boxes. (改为单数句） These are oranges.(改为单数句） These are his brothers 改为单数句 These are English books .（改为单数句 These are English books.改为单数形式 These are dishes 改为单数句 these are my oranges(改为单数句式) Are these orange quilts?改为单数句 are these your books?改为单数形式 These are apples改为单数形式 these are apples 改为单数形式 are these apples?改为单数形式 These are our apples改为单数 Are these sheep怎么改为单数形式 these are our apples改为单数句子 These are your books.(改为单数) these are your keys 改为单数句