1) Derive [A] mineral resources from [B] sedimentary rock [C] is a [D] major modern industrial activity.
2) in the matriculation for postgraduate in a short time is realy a hard nut.
[A] To make high scores[B] To make low goal[C] To the high scores[D] Make the low goals
It is really a hard nut to get high scores in the matriculation for postgraduate in a short time.
3) John admitted that it's always difficult.
[A] for him being on time[B] being on time for him
[C] for him to be on time[D] on time for him
4) It is difficult for me [A] to be concentrating [B] while someone [C] is using [D] a vacuum cleaner.
It took us a great deal of efforts to finish that task.
It made him extremely happy to get contact with his family in Taiwan since they separated more than 40 years ago.
It is quite important for us to read good books during the period of general review(总复习)。
It is not difficult for those who study maths well to pass the exam.
It is very kind of you to help me./It is stupid of him to do such a silly thing.
间或也可用for + there to be 表示(而且there后面的不定式只能是to be)。
It's a great pity for there to be much trouble in the company.
5) We refuse that there are insufficient funds in the great vaults(银行保管库)of this nation.
[A] to believe [B] to be belived
[C] beliving [D] have belived
6) The green turtle has been known over 2,000 miles to return to a nesting site.
[A] in the navigating [B] the navigation [C] to navigate [D] navigation
7) For the [A] first time Venusian scientists managed landing [B] a satellite on the planet Earth, and it has been sending [C] back signals as well as [D] photographs ever since.
8) The day is past when Chinese universities and colleges to give high school diplomas to all who sit through four years of instruction, regardless of whether any visible results can be discerned.
[A] afforded [B] affording
[C] to afford [D] can afford
常见的有：advise,decide, discuss, find out, forget, inquire, know, learn, regard, remember, see, settle, teach, tell, think(=consider), understand, wonder等。这些疑问代(副)词有what, when, where, which, how, whether等,但不包括why,如：
He does not know how to go there
when to speak before strangers.
who(m) to visit.
which one to choose.
You can decide whether to go forward or stay here.
when to see a doctor.
I will show you what to do.
where to go.
how to deal with it.
9) The director of this organization must know .
[A] to manage money, sell his product and beable to satisfy stockholders
[B] managing money, selling, and be able to satisfy the stockholders
[C] how to manage money, sell his product, and satisfy the stockholders
[D] money management, selling and being able to satisfy the stockholders
10) To tell you the truth, I really don't know how deal with a man like him.
[A] can I[B] well[C] to[D] much
3、有时，不定式跟作主语时一样，可由it来代替，而把不定式放到后面去He makes it a rule to take a walk before breakfast.
I think it interesting to play football while it is snowing hard.
We find it difficult to get everything ready before the time you require.
She cosiders it important to make friends with them.
I don't think it necessary to argue with them on this problem.
It is impossible for there to be any more.
Would you like there to be a meeting to discuss the problem?
I expect there to be no argument about this?
He has his own decision of how to do it.
To see is to believe/ To work means to earn a living.
2、另一种情况主语是以aim, duty, hope, idea, happiness, job, plan, problem, purpose, thing, wish等为中心的名词,或以what引导的名词性从句，不定式表语对主语起补充说明作用
His wish is to buy a luxurious car in the near future. / The boss's plan is to start building the skycraper immediately. / What I want to say is to get rid of the plan forever.
11) The function of Louis Sullivan's architecture was providing [A] large uninterrupted floor areas [B] and to allow ample light [C] into the interior [D] .
12) The most important [A] thing is negociate [B] with them about [C] the future of [D] the plant.
3、因为不定式所修饰的名词是不定式的宾语，所以如果不定式动词是不及物动词，那么就要在动词后加上相应的介词He has a lot of trifles to deal with./ I had got no place to live in./That girl has nothing to worry about./the subject to concentrate on. / He has a strict teacher to listen to. / She has four children to look after. / She had a sick mother to live with. / This is the very person to sell your ticket to.
18) Although the lecture had already been on for five minutes, I still was not able to find a chair .
[A] to sit[B] for to sit on[C] to sit on[D] for sitting
4、一些表示企图、努力、倾向、目的、愿望、打算、能力、意向等意义的名词后面要求接不定式作其定语，如：ability, attempt, effort等
19) During [A] the 19th century scientists found [B] that when certain parts of the brain were damaged [C] men lost the ability doing [D] certain things.
20) What is new, however, is the scientific attempt whether other planets beyond our own have given birth to advanced civilizations.
[A] discover[B] discovers[C] discovering[D] to discover
21) Surely her daughter would make an even bigger effort her?
[A] please [B] pleased [C] to please [D] having pleased