(2012·辽宁高考)This machine is very easy . Anybody can learn to use it in a few minutes.
A. operating
B. to be operating
C. operated
D. to operate
网友回答
A. operating
B. to be operating
C. operated
(答案→)D. to operate
解析：选D 考查非谓语动词。在句型“主语＋be＋adj.＋to do”中，常用不定式的主动形式表示被动含义，故选D。