In many countries of Western Europe, the numbers of students in higher education doubled within five-year periods during the 1960s and doubled again in seven, eight, or 10 years by the middle of the 1970s.
第一步：找谓语动词
doubled, doubled
第二步：找从属连词
无从属连词， 但有并列连词and连接两个谓语
第三步：找介词短语
In many countries of Western Europe; of students;in higher education;within five-year periods;during the 1960s;in seven, eight, or 10 years ; by the middle of the 1970s.
第四步：找主干
The numbers doubled and doubled.
第五步：识别修饰关系
In many countries of Western Europe在句首，作状语，修饰后面的整个句子;
of students作定语，修饰the numbers;
in higher education作定语，修饰students;
within five-year periods作状语，修饰doubled;
during the 1960s作定语，修饰five-year periods;
in seven, eight, or 10 years作状语，修饰doubled;
by the middle of the 1970s作定语，修饰 seven, eight, or 10 years。
第六步：处理生词
第七步：根据主干和修饰关系翻译句子
In many countries of Western Europe, the numbers of students in higher education doubled within five-year periods during the 1960s and doubled again in seven, eight, or 10 years by the middle of the 1970s.
在许多西欧国家，大学学生的数量在二十世纪六十年代的五年里翻倍了，并且，在到二十世纪七十年代中期的七八或十年的时间里又翻倍了。
