My grandfather was a teacher. He was the headmaster of a school for boys between thirteen and eighteen. I know that he was a kind and gentle man at heart, because when I was young, he gave me presents, and seated me on his knee, and told me stories. But I believe the boys at his school were afraid of him.
At school, when he walked into a room full of noisy boys, there was silence at once. When he looked at a boy with a certain look in his eyes, the boy went red in the face, and looked down at his shoes. If a boy brought him poor, careless work that was not the best the boy could do, my grandfather would pick up the boy’s book and throw it across the room, shouting, “Do it all again, and bring it back to me in the morning!” If the boy was late, or if he forgot to bring the work, he had to do it again, and again, and yet again. My grandfather never forgot.
He was a very different man at school from the man I saw day by day in his own home.
36. I knew my grandfather was kind and gentle, because _________
A．he was a teacher. 
B．he let me sit on his knee and told me stories.
C．he told me stories about how kind he was
D．he was the headmaster of a school
37. When he looked at a boy in a certain way, the boy ________
A．went red and could not return my grandfather’s look
B．looked back at my grandfather’s red face
C. looked at his shoes to see if they were dirty.
D. went red in the face because his shoes were dirty.
38．When he received poor work, my grandfather _______.
A．would become very angry.    
B．threw the work on the floor, and shouted across the room
C．threw the book at the boy.  
D．went red in the face
39．He was a different man at home because  ________.
A．he didn’t get angry at home as he did at school. 
B．he was not as gentle at home
C．he didn’t throw books about at school like he did at home
D．he did not get angry at home.