Demographic indicators show that Americans in the post war period were more eager than ever to establish families. They quickly brought down the age at marriage for both men and women and brought the birth rate to a twentieth century height __1__ after more than a hundred years of a steady decline, producing the “baby boom.” __2__
These young adults established a trend of early marriage and relatively large families that went for more than two decades and caused a major but temporary __3__ reversal of long-term demographic patterns.
From the 1940s through the early 1960s, Americans married at a high rate and at a younger age than their __4__
Europe counterparts. __5__ Less noted but equally more significant, the men and women who formed __6__ families between 1940 and 1960 nevertheless reduced the porce rate after a __7__ postwar peak; their marriages remained intact to a greater extent than did that of __8__ couples who married in earlier as well as later decades.
Since the United States __9__ maintained its dubious distinction of having the highest porce rate in the world, the temporary decline in porce did not occur in the same extent in Europe. __10__ Contrary to fears of the experts, the role of breadwinner and homemaker was not abandoned.
height可以作“极点，顶点”解释。例如：The height of cleverness is to conceal one’s cleverness。
2. 将第二个不定冠词a 去掉。
steady decline 意为持续的下降，前面不用加冠词。又如：years of hard work。根据语感可以判断出来。
此处是“持续”的意思，所以可以用went on 或者last来表达。
8. 将that 改为those。
10. 将in改为to。短语to the extent是固定搭配。