Sam some knowledge of the puter just by watching others working on it.
A. brought up
B. looked up
C. picked up
D. set up
网友回答
A. brought up
B. looked up
(答案→)C. picked up
D. set up
解析：考查短语辨析。brought up培养，提出，looked up查字典，picked up捡起，偶然学到，set up 建立，句意：山姆只凭看见别人从事电脑工作他就偶然学会了一些计算机知识。故选C。