The weather will keep warm in the days to come.

在未来几天内，天气将持续保持暖和。

(2)中心词是序数词、形容词最高级、the last/the only/the next或被这些词修饰时，用不定式作定语。

Zhang Jian is the first Chinese to swim across the Bohai Sea.

张健是第一个横渡渤海的中国人。

He was the only one to finish the task on time.

他是唯一一个按时完成任务的人。

2.不定式作宾语

(1)有些动词只能跟不定式作宾语，如：agree，ask，aim，attempt，choose，decide，demand，expect，fail，help，learn，manage，offer，plan，prepare，pretend，promise，refuse，seem，hope，wish等。

I decided to buy a walkman to learn English.

我决定买个随身听来学英语。

His brother wished to win the first prize.

他哥哥希望获得一等奖。

(2)有些动词(短语)常用"疑问词＋不定式"作宾语，如：ask，wonder，teach，know，tell，see，learn，hear，explain，decide，show，forget，remember，discuss，find out等。

Mr.Smith didn't know when to leave there.

史密斯先生不知道何时离开那里。

I asked Professor Li how to learn English well.

我请教李教授如何学好英语。

3.不定式作状语

(1)不定式作目的状语。强调时可用in order to do或so as to do。

To conceal my emotion，I buried my face in my hands.

为了掩饰我的情绪，我用手捂着脸。

The bus stopped so as to pick up passengers.

公共汽车停下来以便让乘客上车。

(2)不定式作结果状语。"only＋动词不定式"常表示未预料到的、令人沮丧的结果；so...as to...，such...as to...，enough to以及too...to...等结构中的不定式也表结果。

He lifted a rock only to drop it on his own feet.

他搬起石头砸了自己的脚。

The house is so high and narrow as to resemble a tower.

这房子又高又窄，像一座塔。

He is too young to have seen the bloody war.