they are our animal friends改为单数形式

they are our animal friends改为单数形式 They are his friends改为单数形式 those are green jeeps.改成单数形式 they are our good friends are t They are our friends变单数句 They are my friends.改为单数句 Are those his friends?改为单数形式 are they your gongd friends 改为单数或复数形式.怎么改? They are our good friends改为复数 they are English books.(改为单数形式) They are Chinese【改为单数形式】 are they apples?改为单数形式 they are your sons改为单数形式