资料题：We are told that in an average family about 1900（　）。

The great recent changes have been in the lives of women.During the twentieth century there was an unusual shortening of the time of a woman's life spent in caring for children.A woman marrying at the end of the 19h century would probably have been in her middle twenties,and would be likely to have seven or eight children, of whom four or five lived till they were five years old.By the time the youngest was fifteen, the mother would have been in her early fifties and would expect to live a further twenty years, during which custom, chance and health made it unusual for them to get paid work.Today women marry younger and have fewer children.Usually a woman's youngest child will be fifteen when she forty-five and is likely to take paid work until retirement at sixty.Even while she has the care of children, her work is lightened by household appliances and convenience foods.This important change in women’ s way of life has only recently begun to have its full effectom women' s economic position.Even a few years ago most girls left school at the first opportunity, and most of them took a full-time job.However, when they married, they usually left work at once and never returned to it.Today the school-leaving age is sixteen, many girls stay school after that age, and though women tend to many younger, more married women stay at work at least until shortly before their first child is born.Very many more afterwards return to full or part-time work.Such changes have led to a new relationship in marriage, with both husband and wife accepting greater share of the duties and satisfaction of family life, and with both husband and wife sharing more equally in providing the money, and running the home, according to the abilities and interest of each of them.