動詞不定式作為一種非謂語動詞形式，歷來都是高考的重點和難點。新課標(biāo)高考對這個知識點的考查主要體現(xiàn)在語法填空題和短文改錯題中。同學(xué)們在做題時往往容易把不定式和動名詞、現(xiàn)在分詞混淆，造成使用錯誤。本文結(jié)合近幾年高考題和平時的運用情況歸納了幾種易混易錯的情況。
[不定式符號to和介詞to的混淆]
不定式的考查直接與to相關(guān)。一些固定的句式和短語中都帶有to，同學(xué)們很容易混淆。
例1 （2014·全國卷Ⅰ） It took years of work （reduce） the industrial pollution and clear the water.
解析 to reduce�？疾椴欢ㄊ皆诠潭ň涫街械倪\用。It takes/took some time to do sth.意為“做某事花費多長時間”，故填to reduce。
例2 （2016·全國卷Ⅱ） If you find something you love doing outside of the office， you’ll be less likely （bring） your work home.
解析 to bring�？疾楣潭ù钆涞挠梅�。be likely to do sth.意為“可能做某事”，故填to bring。
to doing sth.這樣的動詞短語不是很多。如：
1. 動詞+介詞to+動名詞
stick to doing sth. 堅持做某事
apply to doing sth. 適用于做某事
object to doing sth. 反對做某事
see to doing sth. 負責(zé)做某事
2. 動詞+賓語+介詞to+動名詞
apply oneself to doing sth. 獻身于某事
have an objection to doing sth. 反對做某事
3. be+形容詞/done+介詞to+動名詞
be used to doing sth. 習(xí)慣于做某事
be opposed to doing sth. 反對做某事
4. 其他結(jié)構(gòu)+介詞to+動名詞
get down to doing sth. 開始做某事
look forward to doing sth. 盼望做某事
[動詞后接動名詞還是不定式作賓語]
例3 （2014·全國卷Ⅱ） I heard a passenger behind me shouting to the driver， but he refused （stop） until we reached the next stop.
解析 to stop�？疾椴欢ㄊ阶鲑e語。句意為：……但司機堅持要到下一站才停車。refuse后接不定式作賓語，意為“拒絕做某事”。
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。事實上，沒有吃食物的狗卻因誤報被主人責(zé)備，他們更易于表現(xiàn)出“內(nèi)疚表情”中的大多數(shù)因素。tend to do“易于、傾向于做某事”，故填to show。
[不定式符號to的省略與否]
不定式符號to常常省略的情況：
1. 不定式用于let，make，have等使役動詞和feel，hear，notice，observe，see，watch，look at，listen to，sense等感官動詞后作賓語補足語時必須省略to。
They made him tell them everything.
We all felt the house shake.
當(dāng)用于被動語態(tài)時，其后必須帶to。如：
He was made to work twenty hours a day.
當(dāng)feel后作賓語補足語的不定式為to be時，不能省略to。如：
They all felt the plan to be unwise.
2. 不定式作介詞except/but的賓語，其前有do，則不定式不帶to；如沒有do，不定式帶to。如：
There’s little we can do except wait.
Wh have no choice but to wait.
3. 主語以what，all，the only thing等開頭的句子中有行為動詞do時，作表語的不定式省略to。
The only thing to do now is （to） go on.
4. 當(dāng)兩個或多個作用相同的不定式并列時，通常第一個不定式用了to時，其余不定式中的to可省略。
It is easier to persuade people than （to） force them.
但如果兩者有對比關(guān)系，則后面不定式前的to不可省略。
To try and fail is better than not to try at all.
5. 為了避免重復(fù)，動詞可以省略，但通常保留不定式符號to。
I shall go if I want to.
但被省略的不定式是to be短語時，則應(yīng)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 寧愿做某事
例5 （2015·浙江卷） The position of the classroom with its view made me felt like I was dreaming.
解析 felt→feel。make是使役動詞，后接動詞原形作賓語補足語，構(gòu)成make sb do sth.結(jié)構(gòu)，意為“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）可以幫助減少免疫系統(tǒng)的疲勞，并使人感到更加精力充沛。allow sb. to do“允許某人做某事”，不定式作賓語補足語，故填to feel。
[作狀語用不定式還是現(xiàn)在分詞]
例7 （2016·全國卷Ⅲ） Skilled workers also combine various hardwoods and metal （create） special designs.
解析 to create。考查不定式作目的狀語。句意：能工巧匠把各種硬木和金屬結(jié)合起來以創(chuàng)造出特殊的裝飾圖案。
例8 （2015·全國卷Ⅱ） 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�？疾椴欢ㄊ蕉陶Z作狀語，表示結(jié)果。
現(xiàn)在分詞做狀語，通常表示時間、原因、結(jié)果、條件、伴隨、方式等。不定式作狀語的情況有：
1. 目的狀語：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. 結(jié)果狀語：常用enough to do， too ... to do， only to do， so ... as to do， such ... as to do結(jié)構(gòu)。
He is too weak to do the work.
�。�1）too之前有only， only too時表示“非�！薄昂堋�。
They are only too lucky to go abroad for a visit.
�。�2）can’t ... too ... “再……也不為過”“越……越好”
You can’t be too careful when crossing the road.
�。�3）在“形容詞/副詞+enough+不定式”結(jié)構(gòu)中表示“足以……”。
He is strong enough to do the work.
�。�4）only to do 結(jié)果，指沒想到，意外。
He hurried home， only to find his house locked.
（5）現(xiàn)在分詞doing也可表示結(jié)果，屬于遞進關(guān)系。
It rained for days， ruining my holidays.
[不定式的時態(tài)]
近幾年的高考題暫時沒有涉及不定式的時態(tài)形式，但同學(xué)們在運用中很容易出錯。
不定式的一般式所表示的動作和謂語動詞所表示的動作同時發(fā)生，或在謂語動作之后，或沒有時間限制；進行式表示正在發(fā)生的動作或與謂語動作同時發(fā)生；完成式所表示的動作在謂語動詞所表示的動作之前。
不定式對應(yīng)不同的時態(tài)適用于以下四種情況：
1. 表示“說，相信，認為”等含義的結(jié)構(gòu)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”等含義的結(jié)構(gòu)中。如：
She seems to have been a teacher for many years.
3. 表示情緒反應(yīng)的詞作表語，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結(jié)構(gòu)中。如：
She happened to be writing a letter in the room when I come in.
He pretended to have finished his homework.
[不定式作定語的語態(tài)]
... by the age of three， most children have the potential （understand） about 1000 words—most of the language they will use in ordinary conversation for the rest of their lives.
解析 to understand。句意：三歲前，大部分兒童已具備理解約1000個詞匯的強大能力——他們將在余生的日常交際中使用這些語言中的大部分。potential后接不定式作定語。
Tu is the first Chinese person （receive） a Nobel Prize in natural sciences.
解析 to receive。句意：屠呦呦是第一位在自然科學(xué)領(lǐng)域獲得諾貝爾獎的土生土長的中國人。person前有the first修飾，要用不定式作定語，故填to receive。
不定式位于所修飾的名詞或代詞之后作后置定語，與前面的名詞或代詞之間常有四種邏輯關(guān)系。
1. 動賓關(guān)系。不定式與所修飾的詞構(gòu)成動賓關(guān)系，如句中有不定式動作的邏輯主語，不定式用主動形式；反之，用被動形式。
He has much more homework to do.
“Do you have clothes to be washed？”his mother asked.
2. 主謂關(guān)系。句子的主語是不定式動作的執(zhí)行者，用主動形式；反之，用被動形式。
He was the first to come but the last to be interviewed yesterday.
3. 同位關(guān)系。不定式與所修飾的詞構(gòu)成同位關(guān)系。
Everyone has the right to vote and to be voted.
4. 動狀關(guān)系。不定式所修飾的詞是time，place，way等時，不定式作目地/方式狀語修飾謂語，動詞構(gòu)成動狀關(guān)系。
Time is limited. We have no time to play. We should first find a place to live.
We should find a way to stop pollution.
還有一些抽象名詞如ability，chance，idea，hope，wish，excuse，attempt等，常用不定式作定語。
The ability to express an idea is as important as the idea itself.
[少數(shù)動詞帶不同的非謂語形式]
1. 動詞allow，permit，advise，suggest等常接動名詞作賓語，用不定式作賓語補足語（除suggest外）。
Smoking is not allowed in the office.
People are not allowed to smoke in the office.
I suggest spending our summer vacation in a seaside town.
但不能說I suggest us to spend our summer vacation in a seaside town。
2. 動詞need， require， want（需要）和deserve等，常接動名詞的主動形式或不定式的被動式作賓語。
The baby needs looking after./The baby needs to be looked after.
Tricycles are worth using/worthy of being used/worthy to be used if you want to explore the narrow hutong of old Beijing.
3. 使役動詞have， let， make和get后接不同的非謂語形式作復(fù)合賓語。如：
have sb. do sth. 讓某人做某事
have sb. doing sth. 使某人持續(xù)做某事
注意 與can’t，won’t連用時，have有“容忍”之意，doing是動名詞，意為“不能容忍某人做某事”。
4. 動詞blame等常用不定式的主動形式作表語，表示被動含義，同學(xué)們易誤用其被動形式。
Officials believe that more than one person may be to blame for the fire.
5. cannot help do sth. 不能幫忙做某事
cannot help doing 情不自禁做某事
6. 感官動詞see，watch，observe，notice，hear等既可帶省略to的不定式做賓語補足語，表示全過程；也可帶現(xiàn)在分詞作賓語補足語，表示正在進行的動作。
Do you hear someone calling for help？