It’s not obvious how the capacity to visualize objects and to figure out numerical patterns suits one to answer questions that have eluded some of the best poets and philosophers.这里的how是既当引导词也当限定词对嘛?
The future of that country is hard to predict________ the economic system is reformed.A. only afterB. unlessC. now thatD. as long as这道题应该选什么?很多答案是C,为什么不能选B?