动词不定式易错点
同学们在做题时往往容易把不定式和动名词、现在分词混淆，造成使用错误。
下面结合典例和平时的运用情况归纳了几种易混易错的情况。
不定式符号to和介词to的混淆
不定式的考查直接与to相关。一些固定的句式和短语中都带有to，同学们很容易混淆。
例1
It took years of work （reduce） the industrial pollution and clear the water.
解析 to reduce。考查不定式在固定句式中的运用。It takes/took some time to do sth.意为“做某事花费多长时间”，故填to reduce。
例2
If you find something you love doing outside of the office， youll be less likely （bring） your
work home.
解析 to bring。考查固定搭配的用法。be likely to do sth.意为“可能做某事”，故填to bring。
to doing sth.这样的动词短语不是很多。如：
1. 动词+介词to+动名词
stick to doing sth. 坚持做某事
apply to doing sth. 适用于做某事
object to doing sth. 反对做某事
see to doing sth. 负责做某事
2. 动词+宾语+介词to+动名词
apply oneself to doing sth. 献身于某事
have an objection to doing sth. 反对做某事
3. be+形容词/done+介词to+动名词
be used to doing sth. 习惯于做某事suggest的名词
be opposed to doing sth. 反对做某事
4. 其他结构+介词to+动名词
get down to doing sth. 开始做某事
look forward to doing sth. 盼望做某事
动词后接动名词还是不定式作宾语
例3
I heard a passenger behind me shouting to the driver， but he refused （stop） until we reached the next stop.
解析 to stop。考查不定式做宾语。句意为：……但司机坚持要到下一站才停车。refuse后接
不定式作宾语，意为“拒绝做某事”。
例4 In fact， dogs that hadn't eaten it but were scolded by the misinformed owners tended ________（show） the most elements of the “guilty look”.
解析 to show。事实上，没有吃食物的狗却因误报被主人责备，他们更易于表现出“内疚表情”中的大多数因素。tend to do“易于、倾向于做某事”，故填to show。
不定式符号to的省略与否
不定式符号to常常省略的情况：
1. 不定式用于let，make，have等使役动词和feel，hear，notice，observe，see，watch，look at，listen to，sense等感官动词后作宾语补足语时必须省略to。
They made him tell them everything.
We all felt the house shake.
当用于被动语态时，其后必须带to。如：
He was made to work twenty hours a day.
当feel后作宾语补足语的不定式为to be时，不能省略to。如：
They all felt the plan to be unwise.
2. 不定式作介词except/but的宾语，其前有do，则不定式不带to；如没有do，不定式带to。如：
Theres little we can do except wait.
Wh have no choice but to wait.
3. 主语以what，all，the only thing等开头的句子中有行为动词do时，作表语的不定式省略to。
The only thing to do now is （to） go on.
4. 当两个或多个作用相同的不定式并列时，通常第一个不定式用了to时，其余不定式中的to可省略。
It is easier to persuade people than （to） force them.
但如果两者有对比关系，则后面不定式前的to不可省略。
To try and fail is better than not to try at all.
5. 为了避免重复，动词可以省略，但通常保留不定式符号to。
I shall go if I want to.
但被省略的不定式是to be短语时，则应保留to be。
He is not the man he used to be.
6. 固定搭配。如：
had better do 最好做某事
would rather do 宁愿做某事
例5
The position of the classroom with its view made me felt like I was dreaming.
解析 felt→feel。make是使役动词，后接动词原形作宾语补足语，构成make sb do sth.结构，意为“使某人做某事”。
例6 So it can help the tiredness out of the immune system and allow people （feel） more energetic.
解析 to feel。它（forgiveness）可以幫助减少免疫系统的疲劳，并使人感到更加精力充沛。allow sb. to do“允许某人做某事”，不定式作宾语补足语，故填to feel。
作状语用不定式还是现在分词
例7
Skilled workers also combine various hardwoods and metal （create） special designs.
解析 to create。考查不定式作目的状语。句意：能工巧匠把各种硬木和金属结合起来以创造出特殊的装饰图案。
例8
When a new day breaks， the walls have given up their heat and are now cold enough （cool） the house during the hot day.
解析 to cool。考查不定式短语作状语，表示结果。
现在分词做状语，通常表示时间、原因、结果、条件、伴随、方式等。不定式作状语的情况有：
1. 目的状语：常用的有to do，in order to do。另外，so as to do和so as to二者均不能位于句首。
She reads China Daily every day so as to improve her Chinese.
2. 结果状语：常用enough to do， too ... to do， only to do， so ... as to do， such ... as to do结构。
He is too weak to do the work.
（1）too之前有only， only too时表示“非常”“很”。
They are only too lucky to go abroad for a visit.
（2）can't ... too ... “再……也不为过”“越……越好”
You can't be too careful when crossing the road.
（3）在“形容词/副词+enough+不定式”结构中表示“足以……”。
He is strong enough to do the work.
（4）only to do 结果，指没想到，意外。
He hurried home， only to find his house locked.
（5）现在分词doing也可表示结果，属于递进关系。
It rained for days， ruining my holidays.
不定式的时态
不定式的一般式所表示的动作和谓语动词所表示的动作同时发生，或在谓语动作之后，或没有时间限制；进行式表示正在发生的动作或与谓语动作同时发生；完成式所表示的动作在谓语动词所表示的动作之前。
不定式对应不同的时态适用于以下四种情况：
1. 表示“说，相信，认为”等含义的结构中。如：
He is said to study abroad next year.
He is said to be writing a novel.
He is said to have passed the driving test.
The book is said to be published next week.
The book is said to have been translated into English.
2. 用在表示“似乎，好像”等含义的结构中。如：
She seems to have been a teacher for many years.
3. 表示情绪反应的词作表语，后接不定式。如：
I'm delighted to hear the news.
I'm sorry to have kept you waiting.
4. 用于pretend/happen to do/to be doing/to have done结构中。如：
She happened to be writing a letter in the room when I come in.
He pretended to have finished his homework.