Americans spend more on fast food than they do on higher education, PCs or new cars—worrying, when a single meal at a KFC of less than a pound-weight of food plus a large Pepsi can top 1,600 calories, not far short of the daily intake recommended by the government for adults doing only “light physical activity”.
破折号前面是比较级结构more…than…，worrying是形容词对前面的总结，when引导状语从句，主语是a single meal of …. plus….，谓语是can top，1600 calories是宾语。后面是形容词结构作定语，recommended by the government for adults是后置定语修饰the daily intake， doing only “light physical activity”是分词结构修饰adults。
short of 缺乏，达不到
When Princeton, the University of Virginia, and Harvard announced last fall that they would drop their early admission options because they gave an unfair advantage to affluent students, many college counselors held their breath.