[讨论]OG11紫皮verbal review第56题

56.  Gortland has long been narrowly self-sufficient in both grain and meat．However, as per capita income in Gortland has risen toward the world average，per capita consumption of meat has also risen toward the world average，and it takes several pounds of grain to produce one pound of meat. Therefore，since per capita income continues to rise，whereas domestic grain production will not increase，Gortland will soon have to import either grain or meat or both．

Which of the following is an assumption on which the argument depends?

(A) The total acreage devoted to grain production in Gortland will not decrease substantially．

(B)  The population of Gortland has remained relatively constant during the country's years of growing prosperity.

(C)  The per capita consumption of meat in Gortland is roughly the same across all income levels．

(D)  In Gortland, neither meat nor grain is subject to government price controls．

(E)  People in Gortland who increase their consumption of meat will not radically decrease their consumption of grain．

这题答案选E没有疑问.

我的问题是:as per capita income in Gortland has risen toward the world average，per capita consumption of meat has also risen toward the world average, 这里的现在完成时, 究竟是表示过去发生的动作(到现在已经结束的动作), 还是从过去开始、一直进行到现在、并将继续进行下去的动作?

如果是前者，我觉得是不是结论还有另一个隐含的assumption:已知事实是, 人均肉类消费量随人均收入的增加而增加.结论说,随着人均收入继续增加, (隐含assumption: 人均肉类消费量也会继续保持原先的趋势, 随之增加), 谷类产品或肉类需要进口.