词汇：
mice n.老鼠 (复数)
bioethicist n.生物伦理学家
sjbling n.兄弟姐妹
注释：
1. brothers and sisters born 50 years apart 出生年份相隔50年的兄弟姐妹
2. We had better not go anywhere near it 我们最好离它远点，这里的it指代前面讲的 anti-ageing technology.
练习：
1.which of the following is NOT mentioned as one of the things that living longer might enable an individual to do?
A)Spending more time with his family.
B)Having more education.
C)Realizing more dreams.
D)Working longer.
2.Which of the following is implied in the sixth paragraph?
A)Marriages in the US today are quite unstable.
B)More and more people in the US today want to get married.
C)Living longer would make it easier for people to maintain their marital ties.
D)If people live longer， they would stay in marriage longer.
3.All of the following are possible effects living longer might have on working life EXCEPT
A)Communication between employers and employees would be more difficult.
B)More money would be used by employees in payment of their employees.
C)The job market would be more competitive.
D)It would be more difficult for young people to be promoted to top positions.
4.An important feature of a society in which people live a long life is that
A)it places more emphasis on educating the young.
B)it is both wise and energetic.
C)it lacks the curiosity to experiment what is new.
D)it welcomes Changes.
5.Which of the following best describes Callahan’s attitude to anti-ageing technology?
A)Optimistic.
B)Pessimistic.
C)Reserved.
D)Negative