A little boy invited his mother to attend his school’s first teacher-parent meeting. To the little boy’s disappointment,she said she would go. This   16   be the first time that his classmates and teacher   17   his mother and he felt ashamed of her   18  . Although she was a beautiful woman, there was a scar(疤痕)that   19  nearly the right side of her face. The boy never wanted to   20  why or how she got the scar.
At the meeting, the people were impressed by the kindness and natural beauty of his mother in spite of the scar, but the little boy was still  21 and hid himself from everyone,  22   a conversation between his mother and the teacher.
The teacher asked   23 ,“How did you get the scar on your face?”
The mother answered,“When my son was a baby, he was in a room that caught fire. Everyone was   24  afraid to go in because the fire was   25   ，so I went in. As I was running toward his bed, I saw a piece of wood coming down and I placed myself over him trying to protect him. I was knocked senseless but   26  , a fireman came in and saved both of us.” She touched（摸着） the   27  side of her face. “This scar will be  28 ,but to this day, I have never regretted what I did.”
At this point, the little boy came out running toward his mother with tears in his eyes. He held her mother in his arms and   29   a great sense of the sacrifice(牺牲)that his mother had made for him. He held her hand tightly for the   30  of the day.

A little boy invited his mother to attend his school’s first teacher-parent meeting. To the little boy’s disappointment(失望), she said she would go. This would be the  16  time that his classmates and teacher met his mother and he  17  lose his face because of her appearance. Although she was a  18  woman, there was a scar(疤痕) that covered nearly the whole right side of her face. The boy never wanted to  19  why or how she got the scar.
At the meeting, the people were   20  by the kindness and natural beauty of his mother even though she had the scar on her face, but the little boy was still embarrassed(尴尬) and hid himself from everyone.   21 , he happened to hear of a talk between his mother and his teacher.
The teacher asked  22 , “How did you get the scar on your face?”
The mother replied, “When my son was a baby, he was in a room that caught fire. 23 was too afraid to go in because the fire was  24 , so I went in.    25 I was running toward his bed, I saw a long piece of wood  26 and I placed myself over him trying to protect him. I was knocked senseless(失去知觉) but luckily, a fireman came in and saved both of us.” She  27 the burned side of her face. “This scar will be there forever, but to this day, I have never  28 what I did.”
At this point, the little boy came out running toward his mother with  29 in his eyes. He held her in his arms and felt a great sense of the sacrifice(牺牲) that his mother had made for him. He held her hand  30  for the rest of the day.

In Chicago, a computerized system has been developed that controls(管理)traffic on the city’s 235 miles of seven expressways. Now one—a controller—can follow the movement of Chicago’s traffic by looking at a set of lights. The system uses electric sensors(感应器) that are built into each expressway, every half a mile. Several times a second, the computer receives information from each sensor and translates it into green, yellow or red lights on a map in the control room. A green light means traffic is moving forty-five miles an hour, yellow means thirty to forty-five miles an hour, and red means heavy traffic—cars standing still or moving less than thirty miles an hour.

  “See that red light near Austin Avenue?”the controller asked a visitor.“That’s a repair truck fixing the road, and the traffic has to go around it.”At the Roosevelt Road entrance to the expressway, the light kept changing from green to red and back to green again.“A lot of trucks get on the expressway there,”the controller explained.“They can’t speed up as fast as cars.”The sensors show immediately where an accident or a stopped car is blocking the traffic, and a truck is sent by radio to clear the road. The system has lowered the number of accidents by 18 percent. There are now 1.4 deaths on Chicago’s expressway for each one hundred million miles traveled, while in other parts of the county there are 2.6.

  Traffic experts say that the Chicago system is the “coming thing”.Systems like Chicago’s are already in use on some expressways in Los Angeles and Houston.“Chicago has taken the lead,”said New York City’s traffic director and he added,“Chicago’s a good example.”

根据短文内容，选择最佳答案，并在答题卡上按要求作答。

1.The passage is mainly about ________ on expressways in Chicago.

  A. the traffic control system                  B. the movement of the traffic

  C. the electric sensors                       D. the traffic lights

2.When the cars move under 30 miles an hour, ________ on the map in the control room.

A. the red light appears                      B. the red light turns yellow

C. the yellow light appears                   D. the green light turns red

3. According to the passage, we may learn __________.

  A. some visitors are traveling on the expressway

  B. there is no heavy traffic on Chicago’s expressways

  C. the traffic on Chicago’s expressways is well managed

  D. the number of accidents in the US has dropped by 18%

4.In Paragraph 2 the underlined word “it” refers to ___________.

  A. the red light                       B. the truck that needs repairing

  C. the traffic                         D. the truck that is fixing the road

5.The writer writes the article mainly by _________.

  A. giving reasons and results           B. giving examples and explaining them

  C. describing what he thinks          D. asking and answering questions