句型转换（5小题，每题1分，共5分）

小题1:Both of his parents prefer to travel around in summer. ( 改为否定句)

     of his parents       to travel around in summer.

小题2:The Bank of China is about 5 minutes’ walk from the zoo. (对划线部分提问)

                is the bank of China from the zoo?

小题3:Sandy really doesn’t know how to deal with this problem. (改为复合句)

Sandy really doesn’t know how               deal with this problem.

小题4:We noticed him eating snacks in class. (改为被动语态)

He                  eating snacks in class by us.

小题5:The news was very exciting and everyone shouted with joy. (合并成一句)

It was                 news that everyone shouted with joy.

下列性质可以证明NaCl是离子化合物的是（　　）

A．可溶于水

B．具有较高的熔点

C．水溶液能导电

D．熔融状态下能导电