Sam some knowledge of the computer just by watching others working on it.A. brought upB. l

问题补充：

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

答案：

A. brought up

B. looked up

(答案→)C. picked up

D. set up

解析：考查动词短语辨析。A抚养，抚育；呕吐；B查找；C捡起，用车接；无意中学会；D建立。成立；句意：Sam通过看别人玩电脑，无意中学会了电脑的知识。根据句意说明C正确。