2011年六级完形填空分类练习（2）

会计考友

　　Sleep is divided into periods of so-called REM sleep, characterized by rapid eye movements and dreaming, and longer periods of non-REM sleep. 41 kind of sleep is at all well-understood, but REM sleep is 42 to serve some restorative function of the brain. The purpose of non-REM sleep is even more 43 . The new experiments, such as these 44 for the first time at a recent meeting of the Society for Sleep Research in Minneapolis, suggest fascinating explanations 45 of non-REM sleep.
4 e" o" ?+ y  O) M　　For example, it has long been known that total sleep 46 is 100 percent fatal to rats, yet, 47 examination of the dead bodies, the animals look completely normal. A research has now 48 the mystery of why the animals die. The rats 49 bacterial infections of the blood, 50 their immune systems-the self-protecting mechanism against diseases-had crashed.
/ k3 A4 R3 w7 _) m　　41. [A] Either [B] Neither [C] Each [D] Any
3 N1 h7 R& j% b/ M7 R　　42. [A] intended [B] required [C] assumed [D] inferred
　　43. [A] subtle [B] obvious [C] mysterious [D] doubtful
) B, ^$ q. O2 x. t/ u　　44. [A] maintained [B] described [C] settled [D] afforded
! A% L4 {1 V" _. f9 h1 n5 l　　45. [A] in the light [B] by virtue [C] with the exception [D] for the purpose
　　46. [A] reduction [B] destruction [C] deprivation [D] restriction
　　47. [A] upon [B] by [C] through [D] with
- N8 b; V+ m4 R1 r- Z% z: D* p. ~  ~! ~　　48. [A] paid attention to [B] caught sight of [C] laid emphasis on [D] cast light on
　　49. [A] develop [B] produce [C] stimulate [D] induce
　　50. [A] if [B] as if [C] only if [D] if only
　　答案：BCCBD CADAB