It is pencil case.改为复数是什么?

It is pencil case.改为复数是什么? It's his pencil case.(改为复数） Exuse me!Is this your pencil case?改为复数形式 This is a pencil case.(改为复数句子） This is my pencil case改为复数形式 this is his pencil case 复数句 It is a pencil-box. 改为复数句是什么? 它后面是______are_______. 这样的 It's my pencil case.和She's her mother's good daughter.改为复数句. pencil case的复数形式是什么? her watch is in the pencil case.改为一般疑问句 it is in the drawer. where it is your pencil-case? not it her is pencil case