阅读理解。
When a close friend dies, it often forces you to consider your own death. The more you have in common
with the friend, the more his death will make you wonder about your own. Sometimes you will naturally say
to yourself, "It could just as easily have been me." Such a death has a way of reminding us how fragile life is,
and it may cause you to reassess (重新评价) the direction of your own life.
Jack's story is a good example. A successful businessman making a lot of money, Jack didn't spend as
much time with his family as he wanted. His job required him to work long hours. But three years ago one
of his best friends, a man who worked in the same office, had a heart attack. He died while celebrating his
daughter's eighteenth birthday in a restaurant. He was only fifty years old.
Not long after his friend's death, Jack started to have a chest pain. Finally he had a good physical check-up.
He received a clean bill of health. But the chest pain continued. He kept thinking of the death of his friend. Jack
thought about how much his friend missed in life and he saw how hard it was for his friend's family to manage
after he passed away.
Jack realized that he didn't want to end up his life that way. He talked his feelings over with his wife and
children, and decided to change his way of life. The family moved to a small town where he started a simple
life. Now he is running a small art gallery (画廊). He is relaxed, and says he has never been so happy in his
life. And he has got no more chest pain.
1. Your close friend's death is _____ to you. [ ]
A. a warning
B. common
C. a direction of life
D. an example
2. The underlined sentence in the third paragraph means "_____". [ ]
A. The doctor didn't write a word on his bill
B. The doctor didn't want Jack to pay for the bill
C. The doctor didn't find anything wrong with him
D. The doctor didn't want to treat his pain
3. His friend's death made Jack _____. [ ]
A. lose much interest in life
B. realize that he missed the friend very much
C. doubt his way of life
D. ill for some time
4. While living in the small town Jack _____. [ ]
A. earns less money
B. gets more time
C. has a happier life
D. does all these mentioned above
S后的属性列数和元组个数分别为 (33) ：π1,4(σ3=6(R×S))= (34) ；R÷S= (35) 。