六、完形填空：

　　It is wellknown that life expectancy is longer in Japan than in most other countries. A recent report also shows that Japan has the longest health expectancy in the world.A healthy long life is the result of improvement in social environment.

　　Scientists are trying to work out exactly what keeps elderly Japanese people so healthy, and whether there is a lesson to be learnt from their lifestyles for the rest of us. Should we make any changes to our eating habits, for instance, or go jogging each day before breakfast? Is there some secret ingredient in the Japanese diet that is particularly benefical to the human body?

　　Another factor contributing to the rapid population aging in Japan is a decline in birthrate.Although longer life should be celebrated, it is actually considered a social problem.The number of older people had doubled in the last half century and that has increased pension and medical costs.The country could soon be facing an economic problem, if there are so many old people to be looked after and relatively few younger people working and paying taxes to support them.

　　Raising the retirement age from 65 to 70 could be one solution to the problem. Work can give the elderly a sense of responsibility and mission in life. Its important that the elderly play active roles in the society and live in harmony with all generations.