典型例题
Charles Babbage is generally considered ___ the first computer.
A. to invent B. inventing C. to have invented D. having invented
答案：C. 一般没有consider+宾语+be以外不定式的结构，也没有consider+宾语+doing的结构，排除A、B、D。consider用动词be以外的不定式作宾补时，一般要求用不定式的完成式，故选C。
3) 有些动词可以跟there +to be的结构。例如：
believe expect intend like love mean
prefer want wish understand
例如：
We didn't expect there to be so many people there. 我们没料到会有那么多人在那里。
You wouldn’t want there to be another war. 你不至于想让另外一场战争发生吧。
