句型转换。（每小题1分，共5分）
They’re on the sofa. (对划线部分提问)
                     my books?
How much is it?(写出复数句)
How much                      ?
She likes ice-cream.(改为一般疑问句)
         she          ice-cream?
He has history on Friday.(改为否定句)
He                      history on Friday.
My birthday is in September. My birthday is on the 21st.(合并为一句)
My birthday is          September          .