[观察例句]
1．Some scientists were determined to help humans realise their dream to explore space.
2．On 12 April 1961，Yuri Gagarin became the first person in the world to go into space.
3．First of all，you must be intelligent enough to get a related college degree.
分析上面的句子：句1和句2中黑体部分是动词不定式用作定语；句3中黑体部分是动词不定式用作状语。
[归纳用法]
一、动词不定式用作定语
1．动词不定式作定语常放在名词或不定代词后面作后置定语，表示尚未发生的动作。
Let us give him something to eat.
让我们给他一些吃的东西。
We have much homework to do tonight.
今晚我们有很多作业要做。
2．名词前有first，last，next，only等词以及最高级修饰时，其后要用动词不定式。
He was the first one to think of the idea.
他是第一个想到这个主意的人。
3．抽象名词attempt，ability，chance，desire，determination，decision，plan，way或不定代词something，nothing等后面常用不定式作后置定语。
But Janis Adkins has the ability and desire to do useful work.
但是詹尼斯·阿德金斯有能力和愿望去做有用的工作。
4．当名词与定语之间存在动宾关系时。
I usually have a lot of meetings to attend.
我通常有很多会议要参加。
She is a nice person to work with.
她是一个很好的合作伙伴。
5．当名词与定语之间存在主谓关系时。
We must find a person to do the job.
我们必须找到一个人来做这项工作。
We need someone to go and get a doctor.
我们需要有人去请医生。
