They are English cars.(改为单数形式)

They are English cars.(改为单数形式) they are English books.(改为单数形式) Those are English cars.改为单数是什么? Are they American cars?（改为单数） are those japanese cars?改为单数形式 They are some English girls改为单数形式是什么? They are English books (5改为单数形式） They are English girls 改为单数形式 __ __English girls They are English watches.(改为单数形式） They are English boys.(改为单数形式） They are English cars改为否定句 They're English books.改为单数形式