In the United States, employees typically work five days a week for eight hours each day. However, many employees want to work a four-day week and are willing to accept less pay in order to do so. A mandatory policy requiring companies to offer their employees the option of working a four-day workweek for four-fifths (80 percent) of their normal pay would benefit the economy as a whole as well as the individual companies and the employees whodecided to take the option.
The shortened workweek would increase company profits because employees would feel more rested and alert, and as a result, they would make fewer costly errors in their work. Hiring more staff to ensure that the same amount of work would be accomplished would not result in additional payroll costs because four-day employees would only be paid 80 percent of the normal rate. In the end, companies would have fewer overworked and error-prone employees for the same money, which would increase company profits.
For the country as a whole, one of the primary benefits of offering this option to employees is that it would reduce unemployment rates. If many full-time employees started working fewer hours, some of their workload would have to be shifted to others. Thus, for every four employees who went on an 80 percent week, a new employee could be hired at the 80 percent rate.
Finally, the option of a four-day workweek would be better for individual employees. Employees who could afford a lower salary in exchange for more free time could improve the quality of their lives by spending the extra time with their families, pursuing private interests, or enjoying leisure activities.
例如上文中，主体段1的主题句是The shortened workweek would increase company profits.
主体段2的主题句是 For the country as a whole, one of the primary benefits of offering this option to employees is that it would reduce unemployment rates.
主体3的主题句是the option of a four-day workweek would be better for individual employees.
这体现在表达公司这一政策时采用的不同表达：The shortened workweek，offering this option to employees, it, the option of a four-day workweek。这些同义替换体现了词汇多样化这一学术写作的要求。
主体段1在主题句后面紧跟了一个原因状语从句，然后用一个并列分句写出了这一选择的结果 (because employees would feel more rested and alert, and as a result, they would make fewer costly errors in their work.)。然后进一步分析雇用更多公司为什么会获得更多利润。
主体段3 扩展时用了一个定语从句 (Employees who could afford a lower salary in exchange for more free time)，实际上这个定语从句相当于一个 if 条件句，后面的主句则是这一选择的结果。
当然，从短文中我们也可以学习到一些好的句式和表达。如 as a result，ensure that ...，result in，one of the primary benefits of is that，if... Thus ... sb who ... would ... by doing ... 这些表达展现了非常好的逻辑关系，这是许多考生欠缺的。