难点18 灵活多用的动词不定式

动词不定式是高考的必考内容之一，其考查内容多且复杂，高考中常考查不定式作主语、状语、宾语、补语、表语和插入语；不定式的时态和语态，主动表示被动意思等；动词不定式符号“to”的省略也在考查范围之内。
●难点磁场
1.(★★★★★)There are five pairs________,but I’m at a loss which to buy.
A.to be chosen from B.to choose from
C.to choose D.for chosing
2.(★★★★)________late in the morning,Bob turned off the alarm.
(2001京、皖、蒙春季高考)
A.To sleep B.Sleeping C.Sleep D.Having slept
3.(★★★★★)It is said that in Australia there is more land than the government knows________. (NMET 2002)
A.it what to do with B.what to do it with
C.what to do with it D.to do what with it

●案例探究
1.Robert is said________ abroad,but I don’t know what country he studied in.
A.to have studied B.to study
C.to be studying D.to have been studying
命题意图：考查动词不定式的时态（完成式）的用法。此题属五星级题目。
知识依托：不定式的完成式表示的动作通常在谓语所表示的动作（或状态）前已完成，强调动作发生在过去。
错解分析：C、D项干扰较大。若选C项，but后句子应改为but I don’t know what country he is studying in.若选D项，应改为：but I don’t know what country he has studied in.
解题方法与技巧：由题干“I don’t know what country he studied in”可得知“他在国外学习这一动作发生在过去”。故答案为A。
答案：A
2.The purpose of new technologies is to make life easier,________ it more difficult.
A.not make B.not to make
C.not making D.do not make
命题意图：考查不定式作表语。此题属四星级题目。
知识依托：句子的表语是两个并列比较的不定式；to do A和to do B两个不定式作比较。后者“to”不可省略。
错解分析：A项干扰性较强，但应掌握to do A和to do B两个不定式作比较，后者to不可省略。
解题方法与技巧：分清句子的基本结构。
答案：B
3.I’ve worked with children before,so I know what________ in my new job.
(NMET 2000)
A.expected B.to expect
C.to be expecting D.expects
命题意图：考查疑问词加不定式的用法。此题属四星级题目。
知识依托：疑问词加不定式可以作主语、表语及用在某些动词后作宾语，相当于名词性从句。这些动词有ask,discuss,decide,explain,forget,find out,know,learn,remember,show, tell,wonder等等。what to expect相当于what I will expect。故答案为B。
答案：B
4.He tried many times to sneak across the border to a neighbouring country,______ each time.
A.having been caught B.unfortunately caught
C.always being caught D.only to be caught
命题意图：此词考查动词不定式作结果状语的用法。此题属五星级题。
知识依托：现在分词和不定式都可作结果状语，前者表示的是顺理成章，自然而然的结果；而不定式作结果状语，有两种情况：
①用来表示“意想不到、突然的结果”。
②用于某些结构中，如“too…to…,so…as to…”。
例：He hurried to the station,only to find the train had left.(意想不到的结果）
答案：D

●锦囊妙计
1.动词不定式也有时态和语态的变化，需牢牢掌握。
2.不定式作定语，应注意：不定式所修饰的名词或代词和不定式能构成逻辑上的主谓关系时，不定式用主动形式。例：
Tom is the right man to do the work.
3.不定式与所修饰的词能构成逻辑上的动宾关系；又与该句主语构成主谓关系时，不定式常用主动形式。如：I’ve got something important to do.
4.在feel,hear,listen to,make等感官动词或使役动词后，常用不带to的动词不定式作宾补，但变被动时，需加上“to”。

●歼灭难点训练
1.(★★★★)The boy wanted to ride his bicycle in the street,but his mother told him________.
A.not to B.not to do C.not do it D.do not to
2.(★★★★)I lost my way in complete darkness and,________ matters worse,it began to rain.
A.made B.having made C.making D.to make
3.(★★★★)They had nothing else to do but________ a doctor.
A.call for B.to send C.to call on D.send for
4.(★★★★★)Tom did whatever he could________ those who were in trouble.
A.to help B.help C.helping D.do help
5.(★★★★★)The way they talked________ the problem seemed impossible.
A.about settling B.to settle
C.of settling D.about to settle
6.(★★★★★)Every minute is made full________ of________ our lessons well.
A.to use;study B.use;studying
C.use;to study D.used;studying
7.(★★★★)—Have you anything________ there.
—No.Thank you just the same.
A.should be taken B.to be taken
C.to take D.which should be taken
8.(★★★★★)The old man was once________ sing the song.
A.listened to B.listening to
C.listened to to D.listen to