文章开头：Half of your brain stays alert and prepared for danger when you sleep in a new place
26. K) referred
27. O) volunteers
28. M) specifically
29. H) novel
30. I) potential
31. E) identified
32. L) species
33. G) marine
34. B) consciously
35. J) predators
D 36. A number of factors are driving down the global oil prices not just for now but in the foreseeable future.
L 37. Pricing carbon proves the most economical way to reduce greenhouse gas emissions.
J 38. It is estimated that extreme weather conditions have endangered the lives of millions of African children.
E 39. The prices of coal are low as a result of over-supply and decreasing demand.
H 40. Higher fossil fuel prices prove to be conducive to innovation and application of cleaner technology.
A 41. If fossil fuel prices remain low for a long time, it may lead to higher emissions of greenhouse gases.
G 42. Fossil fuels remain the major source of primary energy consumption in today’s world.
F 43. Even major fossil exporting countries have great potential to develop renewable energies.
O 44. Greenhouse gas emissions, if not properly dealt with, will pose endless risks for mankind.
B 45. It is urgent for governments to increase the cost of using fossil fuels to an appropriate level to lessen the catastrophic effects of climate change.
46. B) They formulated a dress code with distinctive American features.
47. D) It was a completely new invention.
48. C) Ease of care
49. A) A shift of emphasis from beauty to utility.
50. C) They advocated equity between men and women.
51. D)They have changed the previous migration habits of certain birds.
52. D)They are more likely to be at risk of dying
53. B)They may eat something harmful.
54. C)They are not attracted to the rubbish dumps on their migration routes.
55. A)The potential harm to the ecosystem.