[单项选择]How often one hears children wishing they were grown up, and old people wishing they were young again. Each age has its pleasures and its pains, and the happiest person is the one who enjoys what each age gives him without wasting his time in useless regrets.
Childhood is a time when there are few responsibilities to make life difficult. If a child has good parents, he is fed, looked after and loved, whatever he may do. It is impossible that he will ever again in his life be given so much without having to do anything in return. In addition, life is always presenting new things to the child--things that have lost their interest for older people because they are too well known. But a child has his pains; he is not so free to do what he wishes to do; he is continually being told not to do things, or being punished for what he has done wrong.
When the young man starts to earn his own living, he can no longer expect others to pay for his food, his clothes, and his room, but has t
A. examples of successful young men
B. how to build up one’s position in society
C. joys and pains of old people
D. what to do when one has problems in life