are these old coats 改为单数句

are these old coats 改为单数句 These are some old photos.改为单数句 These are old buses.的单数句 these coats are yeiiow变单数形式 Are these nice pictures 改为单数句 These are his brothers 改为单数句 These are yellow purses.(改为单数句) These are dishes 改为单数句 These are my pencils改为单数句 These are his watch.改为单数句 These are boxes. (改为单数句） These are apple trees(改为单数句)