There was a woman in Detroit,  who had two sons.  She was worried about them, especially the
 younger one, Ben,   1  he was not doing well in school. Boys in his class made jokes about him
 because he seemed so  2 .      
     The mother  3  that she would, herself, have to get her sons to  do better in school.  She told them
 to go to the Detroit Public Library to read a   4  a week and do a report about it for her.        
     One day, in Ben's   5 ,  the teacher held up a rock and asked if anyone knew it.  Ben put up his 
hand and the teacher let him  6 . "Why did Ben raise his hand?" they wondered. "He  7  said anything; 
what could he possibly want to say?"      
     Well, Ben not only  8  the rock; he said a lot about it.  He named other rocks in its group and even 
knew  9  the teacher had found it.  The teacher and the students were  10 .  Ben had learned all this from 
doing one of his book  11 .        
     Ben later went on to the  12  of his class. When he finished high school, he went to Yale University
 and at last became one of the best doctors in the United States.       
     After Ben had grown up, he  13  something about his mother that he did not know as a  14 .       
     She,  herself,  had never learned how to  15 .

     An old friend was going to spend a few days with me. He called from the airport to tell me he had
arrived. I was not able to   1   the office, but I had prepared for his arrival. After telling him my new    2    
address，I told him that I had     3     the key under the doormat (门前的擦鞋垫). I knew it would be
quite late    4     I could get back. He could make    5 at home and eat any food that was in the
refrigerator.
    Two hours later he   6    me from the house. At the moment, he said he was listening to
some of my    7    after having a nice meal. He had found the   8   and cooked some fish and had also
helped himself   9    some juice. He hoped I would    10    him soon. I asked him if he had any difficulty
in finding the house. He answered the   11   problem was that he couldn't find the key under the doormat, but    12    , the living-room window by the apple tree was    13    and he had climbed in through the
window. I listened to all this in great    14    .There are no apple trees outside my windows, but there   15   only one by my neighbor's house !