加强腹股沟管前壁最常用的手术方法是()
A.Bassini法
B.McVay法
C.Ferguson法
D.HA1sted法
E.Shouldice法
参考答案:C
已知化合物A (C4Si4H8)与立方烷(C8H8)的分子结构相似如下图 ,则C4Si4H8的二氯代物的同分异构体数目为
A.3
B.4
C.5
D.6
Sam _____ some knowledge of the computer just by watching others working on it. [ ]
A. brought up
B. looked up
C. picked up
D. set up