不定式作定语一般与被修饰名词有以下三种关系：
（1）动宾关系（所修饰的名词在逻辑上作不定式的宾语）

 
更多例句：
a.She has four children to take care of.
b.I had no place to live in.
c.You just regard me as a thing, an object to look at, to use, to touch, but not to listen to or to take seriously.
你只把我当作一件东西，一件任你看，任你用，任你抚摸的东西，但就是不听我的话，不认真对待我。
d.I gave the kid a comic to read .　我给了那孩子一本连环画看。
e.I have no partner to speak English with. 　我没有伙伴一起练习英文。
不能说成：I have no partner to speak English.*
另外要注意的是，因为不定式已经有逻辑宾语，所以不定式动词后不能再加宾语了，比如不能说：
f.I gave the kid a comic to read it .*
g.She has four children to take care of them .*
（2）主谓关系
被only，last，next，序数词以及形容词最高级修饰的名词常用不定式作定语，所修饰的名词与不定式构成逻辑主谓关系。 （考试重点）
a.I don't think he is the best man to do the job.
我认为他并不是做这项工作的最佳人选。
b. The next train to arrive is from New York.
下一列到达的火车是从纽约开来的。
c.Clint was the second person to fall into this trap.
克林特是第二个掉进陷阱的人。
d.Clint was the only person to survive the air crash.
克林特是这次空难事故中唯一的幸存者。
（3）同位关系（两类名词）

 

 
a.A decision_________stock by one or a few of these large companies may have a very important effect on the market as a whole.
A. buying or to sell
B. to buy or selling
C. buying or selling
D. to buy or sell
正确答案：D。
分析：因为decide后边要接to do，所以名词decision后边也要接to do。所以选D。
b.All our attempts_________the child from drowning were in vain.
A. to rescue
B. having rescued
C. rescue
D. being rescued
正确答案：A。
分析：因为动词attempt后边要接to do，所以名词attempt后边也要接to do。所以选A。
c.According to Darwin, random changes that enhance a species'（A） ability for surviving（B） are（C） naturally selected and passed on to succeeding（D） generations.
正确答案：B，应改为to survive。
分析：因为able后边要接to do，所以名词ability后边也要接to do。