阅读理解。 1 If not, and if right now you're not focusing on this article, your time might be better spent on a short nap (小睡) to boost (促进) your focus and productivity (效率). That's what the National Sleep Foundation says, and it's a message that health education professionals at the University of California at Davis (a city of California, America) have been spreading to their students. 'We're familiar with the benefits of sleep,' said Amelia, a student in sleep and stress at the UC Davis health center. 2 For students, the benefits of increased productivity and focus will help their scores-even though there is no data to back that up. However, research has repeatedly shown that when students have 7-9 hours of sleep, 20-30 minute naps do offer these benefits, 3 So Jason B. Spitzer, a health educator, believes encouraging students to take naps to improve their state of mind-not to mention stay awake during classes - is very important. Health educators discovered that while 33 percent of Davis students didn't nap at all, three-quarters of those who did nap did so for too long-more than 30 minutes. That told the educators that a napping campaign would have to focus on two different populations: 4 Health educators hand out 'nap tools'; they include earplugs (耳塞), an eye mask and a tip card with directions to more messages online. They advertise in the student newspaper introducing napping tips and benefits, and they team with the student government to spread the word on napping during National Sleep Awareness Week. 5 'We want to improve their napping and their sleep quality.' Spitzer said. A. Did you get a complete and restful night's sleep last night? B. non-nappers and long nappers. C. The Davis campaign is still changing every year. D.'We're not familiar with the positive effects of napping.' E. We should try our best to nap when it is necessary. F. Napping is very important to us. G. particularly when taken between the hours of 10 to 11 am or 2 to 4 pm.