[例1]The next morning she found the man______in bed，dead.
A.lying B.lie C.lay D.laying
【解析】答案A。find的宾语后面，用分词或分词短语，起宾语补足语作用。现在分词表达主动，也表达正在进行，过去分词表达被动。
[例2]Charles Babbage is generally considered______the first computer.
A.to invent B.inventing
C.to have invented D.having invented
【解析】答案A。由be considered to do sth被认为做某事，排除B、D。此句只说明发明这一个事实，不定式后用原形即可。而C为现在完成时，发明为点动词一般不用完成时，且此处也不强调对现在的影响，因此不选C。
[例3]The chair looks rather hard，but in fact it is very comfortable to______.
A.sit B.sit on C.be seat D.be sat on
【解析】答案B。如果不定式为不及物动词，其后应有必要的介词。当动词与介词连用时，常位于“形容词+动词不定式”结构的末尾。
[例4]— I usually go there by train.
— Why not______by boat for a change？
A.to try going B.trying to go C.to try and go D.try going
【解析】答案D。why not 后面接不带to 的不定式，因此选D。
[例5]Paul doesn’t have to be made______.He always works hard.
A.learn B.to learn C.learned D.learning
【解析】答案B。make后接不带to 的动词不定式，当其用于被动时，to 不可省略。相同用法的动词还有let，have，see等。
[例6]Tell him______the window.
A.to shut not B.not to shut C.to not shut D.not shut
【解析】答案B。tell sb to do sth 的否定形式为tell sb not to do sth。
[例7]She pretended______me when I passed by.
A.not to see B.not seeing C.to not see D.having not seen
【解析】答案A。pretend 后应接不定式。其否定形式为pretend not to do sth。
[例8]Mrs.Smith warned her daughter______after drinking.