0401
31. The spice cinnamon and the drugs cascara and quinine all come from bark, the protective out layer of stems and roots of woody plants.
选B，是不是应该改为outer,但是out也可以作形容词
34. Astronauts receive extensive training to prepare themselves both physically and psychologically for complexity and rigor of a space mission.
选D，为什么
38. A most useful tool for analyzing the elemental composition of fossils is the
electron probe, a modify electron microscope.
我知道D应该是modified,但是A里面，为什么不是The most?
39. Few substance on Earth equal the beauty of gemstones such as twinkling diamonds, green emeralds, red rubies, blue sapphires, and multicolored opals
否定词后面什么时候应该是复数什么时候是单数？？ | 
