第7题: [单项选择]People think that the pure scientist usually disregards the application of pure science to practical affairs, ________ his attention to explanation of how and why events occur. A. refining B. defining C. confining D. declining 参考答案:C 答案解析:confining是分词短语作状语,补充说明情况。原形意思“限制于……”;refining原形意思“精练”;defining原形意思“下定义”;declining原形意思“衰落,婉言拒绝”。根据句子意
第8题: [单项选择]味觉发育的关键时期() A. 出生后 B. 4~5个月 C. 1~2个月 D. 2~3个月 E. 3~4个月 参考答案:B 答案解析:出生时味觉发育已经很完善,对甜和酸等不同味道可产生不同反应;4~5个月对食物的微小改变已经很敏感,是味觉发育的关键时期。