图文配对。

( )1. Don't draw on the wall.                                 

( )2. Put up your hand when you answer the teacher's questions.

( )3. Don't write like that.                                  

( )4. Clean the blackboard after class.                       

( )5. Don't talk in class.                                    

高速线材的精轧机为确保尺寸精度，其轧制均为无张力的轧制。