Render the sentences into the Passive Voice wherever
possible:  
1.    
A
friend of his has shown me an interesting magazine.


2.    
One
uses chalk for writing on the blackboard.


3.    
I
shall finish my work about seven o'clock. 


4.    
Somebody
has opened the door.


5.    
He
will introduce me to his friends.


6.    
They
did not turn off the light.


7.    
By
the middle of autumn we had planted all the trees.


8.    
Has
anybody explained the rules of the game to you?


9.    
We
were looking at the man with great surprise.


10.    Everybody
laughed at this funny animal.