How often one hears children wishing they were grown-ups and old people wishing theywere young again. Each age has its pleasures and its pains， , and the happiest person is the onewho enjoys what each agegives him without wasting his time in uselessregrets. 

Childhood is a time when there are few responsibilities. If a child has good parents, he iswell fed, looked after and loved. It is unlikely that he will ever again in his life be given so muchwithout having to do anything in return. In addition, life is always presenting new things to thechild — things that have lost their interest for older people becausethey are too well known. Buta child has his pains:He is not so free to do what he wishes to do; he is continually being told notto do things or being punished for what he has done wrong. Therefore, a child is not happy as hewishes to be. 

When the young man starts to earn his own living, he becomes free from discipline ofschool and parents; but at the same time he is forced to acceptresponsibilities. With no one to payfor his food his clothes, or his room, he has to work if he wants to live comfortably. If he spendsmost of his time playing about in the way that he used to as a child, he will go hungry. And if hebreaks the laws of society as he used to break the laws of his parents, he may get himself intotrouble. If, however, he works hard, goes by the law and hasgood health, he may feel satisfied inseeing himself make steady progress in his job and in building up for himself his own position insociety. 

Old agehasalways been thought of asthe worst ageto be; but it is not necessaryfor the oldto be unhappy. With old agecomeswisdom and the ability to help others with advice wisely given.The old can have the joy of seeing their children making progress in life; they can watch theirgrandchildren growing up around them; and, perhaps best of all, they can, if their life has been auseful one, fell the happiness of having come through the battle of life safely and of havingreacheda time when they can lie back and rest, leaving everything to others. 

 The happiest people should be those who______.