A sound scientific theory should be one that ____________ ·works not only under one set of conditions at one time, but also under the same conditions at other times ·does not allow any changes eveunder different conditions ·cabe used for many purposes ·leaves no room for improvement
答案是:单选题 ·The way he uses his tools. ·the difference between scientists and ordinary people ·works not only under one set of conditions at one time, but also under the same conditions at other times
