题目

He was crazy ____ his study when he was young, which contributes ____ his success. in later life. A. for; to       B. about; to       C. about; on       D. for; on   答案：Bbe crazy about sth./sb.常用于口语中，作表语，表示“狂热；热衷”。contribute to “对…的贡献，对…有益”。  如图曲线表示物质跨膜运输的方式，叙述正确的是（ ）A.曲线a可以表示小肠上皮细胞吸收葡萄糖B.曲线b可以表示乙醇跨膜运输的方式C.影响曲线b的因素可以是温度、载体或能量D.以a方式运输的物质不能通过无蛋白质的脂双层膜