They are on the sofa改为单数句

They are on the sofa改为单数句 They are on the sofa.改为单数形式 They are on the sofa 的单数句是什么! They are on the sofa改为否定句 they are on sofa 改成单数句子 The baseballs are on the sofa.(改为否定句) They are on the sofa.是什么意思? 原句They are behind the sofa. they的单数是什么 顺便帮我改一下这个句子They are on the desk改为单数句( ) （ ）on the 连词处句 are,not,are,your,now,they,sofa,on,earphones,the,no,ther there are some books on the desk改为单数句 there are some oranges on the table.改为单数句