Are they the twins sweaters?是哪处错误

Are they the twins sweaters?是哪处错误 they are ( ) a.the twins b.twins The sweaters are_sale.They are very cheap. Look!The twins _____ new sweaters. They are -------They are twins. are the twins on the playground? yes, they are They are twins .H( ),they don't look the same they are twins and they have the same ____ The two girls are twins.I think they are Lucy and Lily are twins.they are the s___age. B______of the twins are funny and they are b______students. they are twins ,they names are lucy and lily .这句话有什么错误么