【单选题】According to the first two paragraphs,
A.
the rich countries are the main victims of the economic cr.
B.
people are less likely to associate world's economic downturn with the poorest.
C.
the income in the developing countries has been increasing in recent years.
D.
the size of the world economy will be unchanged by 2010.
【简答题】视觉细胞从形状和功能上可分______________和_______________两种。其中前者主要感知物体的______________,它与_______视觉有关;后者主要感知物体的 ,它与_______ 视觉有关。
【简答题】t_______ adv. 典型地,通常
【单选题】顽拗性种子是不耐失水的,它们在储藏中忌( )