句型转换。

1. Please be very quiet in the classroom. (改为否定句)

    Please______very quiet in the classroom.

2. I like dolphins because they are friendly. (对画线部分提问)

    __   _    you like dolphins?

3. Where do you come from? (改为同义句)

    Where_____you ____  ?

4. We can't finish the work without your help.(用 if 变换句子)

    We can't finish the work_____you_____us.

5. There is a football club near here. (改为一般疑问句)

               a football club near here?

(45) 是同一个变量被用来标识不同的功能，从而通过上下文以决定一个类所代表的功能。一个类型是另一个类型的子类型，这种多态叫 (46) 。

（45）处填（）。

A．参数多态

B．包含多态

C．过载多态

D．强制多态