职称英语卫生类C级:概括大意More Than 8 Hours Sleep（二）

　　4. Paragraph 6___.

　　A. Keprike’s research tool

　　B. Dangers of Habitual shortages of sleep

　　C. Criticism on Kripke’s report

　　D. A way of overcoming insomnia

　　E. Sleep problems of long and short sleepers

　　F. Classification of sleep problems

　　5．To get a good night’s rest，people may not need to ___.

　　6．Long sleepers are reported to be more likely to___.