一家剧院计划在秋季的7周内上演7个剧目，它们是F、J、K、O、R、S。每周上演一个剧目，每个剧目恰好演出一周。剧目的安排必须满足以下条件：
(1)G必须在第三周上演。
(2)O和S不能连续演出。
(3)K必须安排在J和S之前上演。
(4)F和J必须安排在连续的两周中演出。
如果把S安排在第六周，那么必须把R安排在哪一周（）。
A．第七周。
B．第五周。
C．第四周。
D．第二周。
参考答案：A
解析：
已知G安排在第三周，S安排在第六周。则根据条件(4)可知，F和J只能安排在连续的两周中，即第一、二周或者第四、五周。又根据条件(3)可知，K要在J之前，即F和J只能安排在第四、五周，位置可以互换，K安排在第一周或第二周。又根据条件(2)可知，O和S不能连续演出，即O不能安排在第七周，只能安排在第一周或第二周。综上知，R只能安排在剩余的第七周。即正确答案为A。
| 完形填空。 | ||||
| A little boy invited his mother to attend his school's first teacher-parent meeting. To the little boy's 1 , she said she would go. This 2 be the first time that his classmates and teacher 3 his mother and he felt ashamed of her 4 . Although she was a beautiful woman, there was a scar (疤痕) that 5 nearly the right side of her face. The boy never wanted to 6 why or how she got the scar. At the meeting, the people were 7 by the kindness and natural beauty of his mother in spite of the scar, but the little boy was still 8 and hid himself from everyone, 9 a conversation between his mother and 10 . The teacher asked 11 , "How did you get the scar on your face?" The mother answered, " 12 my son was a baby, he was in a room that caught fire. Everyone was 13 afraid to go in because the fire was 14 , 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 15 , a fireman came in and saved both of us." She touched (摸着) the 16 side of her face. "This scar will be 17 , but to this day, I have never 18 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 19 a great sense of the sacrifice (牺牲) that his mother had made for him. He held her hand tightly for the 20 of the day. | ||||
|
