Charles babbage is genrally considere      the first computer
    A.to invent               B.inventing
    C.to have invented        D.having invented
    
    此题设计精巧，迷惑性强，很容易让考生上当。本题旨在考查consider之后的非谓语动语形式。许多考生都记得consider doing表示“考虑做某事”，也有些考生知道consider sb.to be 这个句型表示“认为某人怎么样”，由引，前者选择了答案B,后者则选择了A。其实，这道题的正确答案应为C，原因分析
    一、在动词
    think,conside,believe,sup_pose,know,feel,find,imagine等这类动词之后可由不定式宾补，但不定式短语多为to be 形容词/名词。例如：
    I consider him to he the best candidate 我认为他是最合适的候选人。
    They believd these rules to be important 他们认为这些规则很重要。
    Many people suppose him to be dead 很多人都认为他死了。
    She imagined herself to be superior to others 她自认为比别人都高明。
    He proved himself to be a capable general 他证明了自是个能干的将军
    People think him to be a good cadre 人们公认他是好干部
    以上诸例中都用to be 名词/形容词作宾语补足语，若把to be 省去，即成了形容词或名词作宾补。在consider ,think,find imagine 等词后常用这种结构。例如：
    We consider him our friend 我们认为他是我们的朋友。
    The boy likes to imagine himself a flyer 那个男孩喜欢想象自己是个飞行员。
    They found the answer quite satisfactory
    他们对此答复感到很满意。
    注意：在以上诸例中，我们很少找到to do (其他动词)作宾补的情况。若用其它动词，偶尔见到用完成式。
    I consider him to have acted disgracefully 我认为他表现得不得体。
    二、在下列被动结构中可以用to be ,to do ,to be doing ,to have done 或to have been done  作主语的补足语。
    1、he is thought be honest (=It is thouht that he is homest  )人们知道他是诚实的。
    2、he is said to he from a poor pearant family (=it is said that he is from a poor peasant family )据说他出身于贫农家庭。
    3、life there is said to be quite cheap 据说那里的生活开支相当便宜。
    4、the great wall is said to be 12,000lilong 据说长城长达12，000里。
    5、the country is known to be rich is nat_ural resources 据了解这个国家有丰富的自然资源。
    6、you are supposed to know the laws of your own country 你应该懂得你们本国的法律。
    以上例句中的to be 和to do 不强调时间，或者是一般情况，因此，均用一般式。
    7、he is thought to be hiding in the woods (=peple think that he is hiding is the woods )
    人们认为他正躲藏在树林里。
    8、he is supposed to be washing the car (=he should be washing the car )他应该正在刷车。
    9、they are said to be resrarching into the question 据说他们正在研究这个问题。
    以上三例to be doing 均表示正在进行的动作，故用了动词不定式的进行式。
    10、At leat one policeman was said to have been injured in the accident 据说，在这次事故中至少有一名警察受伤。
    11、they are believed to have landed in America (=it is believed that they have landed in America )人们相信他们已经登上下了美洲大陆。
    12、they are supposed to have discovered America (=it is thought that they have dis_covered America )人们认为他们已经发现了美洲。
    13、the new building was said to have heen built from their own designs 据说这幢大楼是他们自行设计建造的。
    以上四例，强调不定式动作先胃语动语动作，即用了完成式（如例11、12）；强调动作事先已被完成，即用了to have been done 结构，如例10、13。
    综上所述，高考题正是采用了在被动结构中用to have done 作主语补足语的结构（如例11、12）因此，正确答案为C 。