问题
选择题
Computers can do nothing．But once ______what to do, they show extraordinary power to do a great deal．
A．to program
B．being programmed
C．programmed
D．having programmed
答案
答案：C
考查非谓语动词。动词program和逻辑主语they之间是动宾关系，且program发生在主句动词之前，要用过去分词表被动和完成，所以选C。