长难句分类：
　　1. 插入语
　　通常做解释说明作用
　　eg. Inventors are now working on new devices that would be fully placed, along with a tiny power pack, in the patient's chest.
　　In the past, making structures quake-resistant meant firm yet flexible materials, such as steel and wood, that bend without breaking.
　　2. 并列结构
　　(1) 句子和句子的并列
　　由标点符号（如分号；冒号：）或连接词连接的两个简单句的句子的并列（前后出现两个实意动词）
　　eg. We asked them to tell us whether each samples was Coke or Pepsi; then we analyzed the records statistically to compare the participants' choices with what mere guess-work could have accomplished.
　　We encourage our pupils to use the library, and we teach them the skills they need in order to do this efficiently.
　　Having made a choice within these limits we can have certain alterations made, but apart from minor adjustments, we tend to be limited to what the stores have on their racks.考试大－中国教育考试门户网站(www.233.com)
　　(2) 句子成分的并列（前后出现两个相同或相似结构或成分）
　　eg. He quickly found that children as young as four months would learn to turn their heads to right or left if the movement "switched on" a display of lights-and indeed that they were capable of learning quite complex turns to bring about this result, for instance, two left or two right, or even to make as many as three turns to one side.
　　Statuses are marvelous human inventions that enable us to get along with one another and to determine where we "fit" in society.
　　When you come to think of it, only a woman is capable of standing in front of a wardrobe packed full of clothes and announcing sadly that she has nothing to wear.
　　(3) 句子并列与句子成分并列共存
　　eg. For most people the sea was remote, and with the exception of early intercontinental travelers or others who earned a living from the sea, there was little reason to ask many questions about it, let alone to ask what lay beneath the surface.
　　If we look at man as an animal and try to analyze the environmental forces that are acting on the organism, we find that we have to deal with things like climate, soil, plants, and such-like factors common to all biological situations; but we also find, always, very important environmental influences that we can only class as "cultural", which modify the physical and biological factors
　　3. 复合句
　　(1) 名词性从句
　　主语从句及it形式主语
　　eg. So where we hear this debate is primarily in political circles and in the media-not in corporate board rooms or on college campuses.
　　What the doctor at Beth Israel has in the primary nurse is a true colleague.
　　But it used also to be widely believed that effective rewards, at least in the early stages, had to be directly related to such basic physiological "drives" as thirst or hunger.
　　宾语从句及it形式宾语
　　eg. We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere, working in a space laboratory.
　　I think it certain that in decades, not centuries, machines of silicon will arise first to rival and then exceed their human ancestors.
　　表语从句
　　eg. The time of day when you feel most energetic is when your cycle of body temperature is at its peak.
　　The first time that the question "What is at the bottom of the oceans?" had to be answered with any commercial consequence was when the laying of a telegraph cable from Europe to America was proposed.
　　同位语从句
　　eg. At the early attempts, the cable failed and when it was taken out for repairs it was found to be covered in living growths, a fact which defied contemporary scientific opinion that there was no life in the deeper parts of the sea.
　　The way people hold to the belief that a fun-filled, pain free life equals happiness actually reduces their chances of ever attaining real happiness.
　　(2) 定语从句
　　that引导
　　eg. People will be alert and receptive if they are faced with information that gets them to think about things they are interested in.
　　If teacher and learner roles are not interchangeable, what then can be done through teaching that will aid the child in the quest for knowledge?
　　疑问词引导
　　eg. In the 1840s, Maury had been responsible for encouraging voyages during which soundings were taken to investigate the depths of North Atlantic and Pacific Oceans.
　　The problem then arises as to the point at which one can say that these imitations can be considered as speech.
　　同时出现that和疑问词的句子
　　eg. A reporter who has visited plants throughout Europe has an impression that the pace of work is much slower here.
　　Then she writes a care plan centered on the patients illness but which also includes everything else that is necessary.
　　(3) 状语从句
　　eg. Much family quarrelling ends when husbands and wives realize what these energy cycles mean, and which cycle each member of the family has.(时间)
　　But in actual practice this system breaks down in many ways, because the organism and the environment are constantly interacting so that the environment is modified by the organism and vice versa.(原因)
　　A breakthrough in the provision of energy from the sun for the European Economic Community could be brought forward by up to two decades, if a modest increase could be provided in the EEC's research effort in this field, according to the senior EEC scientists engaged in experiments in solar energy at EEC's scientific laboratories at Ispra, near Milan.(条件)
　　Some of my colleagues and I once interviewed and followed approximately 500 terminally ill patients in order to find out what they could teach us and how we could be of more benefit, not just to them but to the members of their families as well.(目的)
　　(4) 含有诸多that的混合复合句
　　eg. Researchers have established that when people are mentally engaged, biochemical changes occur in the brain that allow it to act more effectively in cognitive areas such as attention and memory.
　　4. 倒装句
　　eg. But rarely is success so mysterious.
　　Pinned to their drawing boards are blueprints for improved quake-resistant buildings.
　　Should you break the rule against staring at a stranger on an elevator, you will make the other person exceedingly uncomfortable, and you are likely to feel a bit strange yourself.
　　5. 强调句
　　eg. It is precisely this kind of conversation that is of importance when we are seeking to develop our reading to meet the new demands being placed upon us by studying at a higher level.
　　It was to Maury of the US Navy that the Atlantic Telegraph Company turned,in 1853, for information on this matter.
　　6. 双重否定句
　　eg. If a patient at Beth Israel is not responding to treatment, it is not uncommon for his nurse to propose another approach to his doctor.
　　No school I have taught in has ever ignored spelling or considered it unimportant as a basic skill.
　　7. 省略句
　　eg. Called smart buildings, the structures respond like living organisms to an earthquake's vibrations.
　　8. 现在分词与过去分词作定语
　　eg. In addition, changes made to the construction codes in Los Angeles during the last 20 years have strengthened the city's buildings and highways, making them more resistant to quakes.
　　The next test was more complex, requiring all to scan sequences of 20 identical letters and respond the instant one of the letters transformed into a different one.考试大论坛
　　A decade ago, adapting the infrared scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress.