阅读一篇托福文章多久算合格
其实根据托福阅读是否遇到加试有一定关系，托福阅读的时间也是不一定的，但是基本上我们做阅读的时候一篇最好不能超过20分钟，也并不会严格计时每一篇阅读的答题时间的。下面大家看一些具体的分析吧!
阅读一篇托福文章多久算合格
阅读部分：3——5篇学术文章，每篇700字左右，每篇12-14个问题，时间60-100分钟。大至上也要3到4个小时如果仍有问题可上。对于无加试的阅读部分，变化前后的时间总量没有变化，都是60分钟，对于有加试的阅读部分，变化之前是一篇阅读和两篇文章再加加试的两篇文章，时间总量为100分，变化之后是一篇阅读和两篇文章再加加试的一篇文章，时间总量为80分钟，加试的文章量由以前的两篇变为了一篇。
各篇之间不再单独计时
变化之前考试时间比较死板，第一篇文章必须在20分钟以内做完，等到第一篇文章做完后才能继续在后40分钟做后面两篇文章，有加试的考生还必须等把第二次的两篇文章做完后，才能继续做加试部分的题，如果各部分超过时间还没有做完的题，就不能算入成绩。变化之后考试时间更为灵活，没有加试的考生有60分钟的考试时间做三篇文章，有加试的考生有80分钟的时间做四篇文章，没有强制规定先做哪篇后做哪篇。
提醒各位同学：考试做第一篇文章，不要超20分钟
有一些考生必须把文章一字不漏的阅读和翻译之后才能做题，往往忽视了阅读的速度，这种细读的方法之适用于两种情况：一种是这篇文章是你曾经读到过的，即使一字一句的读也不会花太多时间，另外一种是考生已经具备相当强的阅读水平，而且长期运用这种方法。
很多人都认为词汇题的做的好不好完全取决于自己的词汇量，事实上词汇量是占了相当一部分比重，但是不知道大家是否有过这样的经历，有时候不认识的词经过对上下文的理解和分析也可以作对，反而是那些认识的词汇经常出错，这是因为大家在面对自己有把握的词汇时，往往忽略了上下文的重要性，凭感觉选出了一个自认为理所当然的答案。所以，做好词汇题的关键就在于透彻分析上下文，有时候，个别词汇题也许需要在文章其他段落寻找线索。
其实阅读部分不仅是测试大家对托福文章的理解，还包括阅读的速度，这两方面都不能被忽视，光是具备扎实的基础还远远不够，还需要搭配运用巧妙的做题技巧才能取得阅读高分。
例如当你看到一篇文章，首先要扫一下第一段，看看文章的难易程度，一般情况，平均每篇文章用时11分钟左右，5篇文章中一定有2篇难度稍微大一些，所以首先定位文章的难度和分数的比重，有助于合理的安排做题时间，以便在相同的时间内拿到最多的分数。
总的来说，这次结构的调整对我国学生来说是一件利好的事，取消了规定时限做一篇文章的方式，更符合中国学生的做题习惯，同时，加试部分减少了一篇文章也在一定程度上降低了考试 的难度。在考试中，考生最好快速对考题进行难易度判断，先从简单的文章入手，把时间尽量留给较难的文章，如果第一篇文章只花费了10分钟，那么后面的空余时间就较多。如果某一个题目不能马上解答，可以先跳过，最后再回来处理。
新托福阅读背景知识：梦的背景
梦的背景知识
1953年，美国芝加哥大学，柯立行曼教授和他的研究生阿赛斯基(Reitman’s & Asterisk)正在用脑电波测量的方法研究睡眠，阿赛斯基负责观察被试----是一些婴儿----睡眠时的脑电图。阿赛斯基也许是个很细心的人，再不然就是婴儿可爱的面庞吸引了他。他在观察脑电图的同时，还看了婴儿的脸，遇然间他发现，每当脑电上波出现快波时，婴儿的眼球就会快束速运动，仿佛闭着眼睛在看什么东西。
这是怎么回事?柯立特曼和阿赛斯基猜想这或许和梦有关。他们把一些成人被试带到实验室里，在他们头上接到电极，然后让他们睡觉。当脑电图出现快波时，他们的眼球也开始了快速运动。柯立特曼和阿赛斯基急忙唤醒他们，问他们是否做梦，他们回答说：是的。
而当没有快速眼动的时候，被叫醒的被试大多数都说自己不是正在做梦。
由此，人们发现，梦和脑电图的快波和快速眼动是相联系的。
研究发现，一夜的睡眠过程是两种睡眠的交替，在较短的快波睡眠后，是时间较长的慢波睡眠，然后又是快波睡眠，如此循环。慢波睡眠又可划分为4个阶段或称4期。因此更具体他说，睡眠的程序是：觉醒→慢波、期→2期→3期→4期→快波睡眠，为第一个周期，然后再次重复慢波睡眠期→2期→3期→4期→快波睡眠，如此循环。一般从一次快波睡眠到下一次快波睡眠的间隔时为70-120分钟，平均90分钟。一夜大致要循环4-6次。越到后半夜，快波睡眠越长、越慢睡眠越短。
由于快波睡眠期是人做梦的时期，我们由睡眠过程的脑电图可推断，一个人每夜一般会做4-6个梦，前半夜的梦较短，后半夜的梦较长。根据研究，整夜共有约1-2小时的时间人是在做梦。
由于每个人正常睡眠时间都超过一个循环的时间，由此可知每个人每晚都要做梦。有些人自称自己睡觉从不做梦，是因为他醒来后把夜里的梦忘记了。
早期的研究者们假设，只在在快波睡眠时才有梦。但是近斯的研究却发现，慢波睡眠期也有梦。慢波睡眠的梦不像一般的梦那样由形象构，也不像一般的梦那么生动富于象征性。例如，一个从慢波睡眠中刚醒来的人会说“我正在想着明天的考试”，研究者还发现，大多数的梦游和梦话都是出现在慢波睡眠期。
脑电波可以指示出人是否在做梦，因此脑电波测测量是研究梦的一个主要手段。
但是脑电波却不能说明梦和睡眠的生理机制，更无法告诉我们梦是什么，关于梦的生理机制目前还有极少研究，但是对睡眠的生理机制却有很多的研究，这对我们的理解梦有一定的参考性价值。
早期的生理学家巴甫洛夫认为：睡眠就是大脑皮层神经活动停止，也即所谓抑制。梦是大脑皮神经活动停止时，偶尔出现皮层比做一个燃烧的火堆，那么按巴甫洛夫的观点，睡眠就是这堆火熄灭了，而梦就是在木炭灰烬中偶尔亮起来的火星。
近十几年来，通过对睡眠的生活机制的研究，人们知道巴甫洛夫的观点是不准确的。睡眠不是觉醒状态的终结，不是神经活动的停止或休息，而是中枢神经系统中另一种形式的活动，是一个主动的过程。
脑具有一种负责清醒----转换的中枢，即网状系统。这是脑于中一群弥散的神经核团，当它受到刺激时会使熟睡者醒过来。而当实验者破坏了实验动物的网状系统是时，这个动物就会从此“一睡不醒”。
网状系统的活动受到来自上下两方面的神经冲动的影响。上方，大脑皮层的活动会影响它，因此思虑过多忧心忡忡的人会失眠。下主，来自感觉器官的神经冲动影响它，因此噪杂的声音也会干扰人们的睡眠。除此之外，网状系统的活动还受到两个神经中枢的控制，一个叫中缝核，另一个叫蓝斑。中缝核可导致慢波睡眠。蓝斑则导致快波睡眠，从而与梦有关系。
蓝斑产生的神经兴奋，主要通过脑的视神经束。也许，这和人在梦中所见到的景色有关。另外，蓝斑可能也起着在睡眠中抑制身躯运动的作用。
研究脑生化的科学家发现，中缝核产生的神经递质主要是5--羟色胺。在电损毁动物中缝核前部后，脑5--羟色胺含量大减，同时，动物的慢波睡眠也明显减少，如果把5--羟色胺直接射到动物的中缝核，则动物的慢波睡眠延长，可见5--羟色胺和慢波睡眠有关。
蓝斑区域可产生去甲肾上腺素，它与快波睡眠有关。在损毁动物蓝斑中后部时，去甲肾上腺素减少。同时，快波睡眠也减少。
去甲肾上腺素不仅与快波睡波有关，与觉醒状态的维持也有关。当脑内去甲肾上腺素含量增加是，实验中的动物会从睡梦中醒来。
同生物的研究，似乎可以引向这样一种推测，快波睡眠和觉醒有相似之处，当然，快波睡眠和觉醒决不是一回事。首先就是快波睡眠时运动是被抑制的。但是，和慢波睡眠相比，它和觉醒状态在表现上共性还是稍多一些。它也有较多的心理活动。
对睡眠，特别是与梦有关的快波睡眠的生理层面的研究，使我们对梦的作用有了一定的理解。如果用药物或其它技术抑制快波睡眠，被试者的注意、学习记忆功能就会到损害，同时，情绪会变得焦虑，愤怒，并造成处理人际关系能力下降。由此提示，梦对改善学习与记忆，对改善情绪和社会能力可能有作用。
还有一些研究也发现，快波睡眠和梦可能与新信息的编码有关。一些没有见到过的新形象在梦里得到“复习”和“整理”，然后存入长时记忆库中去，根据这种假说，婴儿每天见到的新东西多，所以就需要多做梦，老年人难得会见到什么新东西，因此就不必多做梦。实际上，婴儿快波睡眠的时间占总睡眠时间的比例也确实远大于老年人。实验也发现，在环境丰富的条件下饲养大白鼠快波睡眠的总时间和百分比都比其它大白鼠更长更多。由此提示，至少“复习整理新形象和新知识”是梦的作用之一。
新托福阅读背景知识：汉谟拉比法典
The code of Hammurabi
Hammurabi was the ruler who chiefly established the greatness of Babylon, the world's first metropolis. Many relics of Hammurabi's reign ([1795-1750 BC]) have been preserved, and today we can study this remarkable a wise law-giver in his celebrated code . . .
by far the most remarkable of the Hammurabi records is his code of laws, the earliest-known example of a ruler proclaiming publicly to his people an entire body of laws, arranged in orderly groups, so that all men might read and know what was required of them. The code was carved upon a black stone monument, eight feet high, and clearly intended to be reared in public view. This noted stone was found in the year 1901, not in Babylon, but in a city of the Persian mountains, to which some later conqueror must have carried it in triumph. It begins and ends with addresses to the gods. Even a law code was in those days regarded as a subject for prayer, though the prayers here are chiefly cursing of whoever shall neglect or destroy the law.
Yet even with this earliest set of laws, as with most things Babylonian, we find ourselves dealing with the end of things rather than the beginnings. Hammurabi's code was not really the earliest. The preceding sets of laws have disappeared, but we have found several traces of them, and Hammurabi's own code clearly implies their existence. He is but reorganizing a legal system long established.
新托福阅读背景知识：植物适应沙漠
Plant adaptation to the desert(背景材料)
Cactus adaptations.
The secret to the superior endurance of cacti lies in their adaptations. Over millions of years, through natural selection, only the strongest and best adapted species survived.
As you know, it is very dry in the desert. Plants that adapt to this are known as xerophytes (from zeros, dry and python, plant). There are plants that avoid the dry season by sprouting from seed just after the spring rain and growing very fast so that by the time the dry season comes, they have already produced a lot of seeds and died. These seeds lie on the soil for the dry season and sprout again in spring and the cycle repeats. Other xerophytes simply drop their leaves and stay dormant for the winter. But there is another special type of xerophytes which stores water in its fleshy tissues. Such plants are called succulents (from success, juicy). The cactus is a typical example of a succulent.
If you cut a cactus open, you see a juicy, slimy tissue. This is where the moisture is stored for the dry season. The part between the middle circle (and pith) and just under the very green part of the plant (or palisade parenchyma) just under the skin is allocated for the storage of water and food for the plant. This is a type of spongy parenchyma and can take up to 85% of the plant's volume. This is a major adaptation in the desert. Because the plant remains completely alive during the dry season and there is no need for it to dry up and lose everything, makes it possible for the plant to grow to large sizes. Another advantage is that the plant retains supplies (in the form of starch) for the winter so that it can flower right away in spring without accumulating more supplies (as most plants need to do in spring). The whole purpose of storing supplies for the winter is mostly to energize flowering in spring but it also lets the cactus start growing much sooner.
Flowering plants breathe and transpire (evaporate water from their surface) through closeable microscopic pores called stoats on the leaves or stems. To do this, their pores have to be open. In most plants these are open all day and on warm nights. But for cacti this is inconvenient as in daytime it is very hot and thus the plant would lose a lot of water through evaporation. So the cactus must close them in the daytime. But then it cannot breathe or photosynthesize (the process where sugars are made from carbon dioxide and water and releasing oxygen using the sun's energy). Succulents have an adaptation to that. Their stoats are closed during the day and are open at night, when it is not that hot and store carbon dioxide in its tissues as crass lean acid and then turn it back to carbon dioxide in the daytime. This process is called crass lean acid metabolism or CAM and it is a very smart way of respiring in the desert.
If we look at the outside of the plant, we notice that there is a tough leathery skin covering the plant, we can also notice the presence of ribs and spines and sometimes fur. These are all very smart adaptations. They serve mainly for surviving heat but are also used as defense.
The tough leathery skin is very impermeable to water, thus reducing evaporation from the surface of the plant. This skin often has a layer of plant wax on it which is often lightly colored (Pilosocereus azures is an example of a plant with such wax), white or blue. This reflects light and also reduces evaporation from the inside.
The ribs are special structures that are also used for enduring extreme heat. The ribs (and spines) trap wind so that the plant is enveloped in a layer of extremely still air, and this is a very important factor in reducing evaporation. On very windy days even the ribs don't help and cacti sometimes wilt because of high water loss.
The spines have different functions. They not only help shade the plant from the sun but are also known to help the cactus absorb water. They do it like this. On cool nights, dew settles on the spines of the plant. The spines are actually known to draw droplets of water towards the areole (the point out of which the spines grow) and here the droplets are absorbed. You can try this at home. Spray the plants with a very fine mist of water and watch what happens to the droplets that settle on the spines. They literally get attracted to the areole along the spine. The spine's structure allows them to do this. Even spines pointing downwards seem to suck the droplets up themselves.
Adaptation features are visible in this Pilosocereus glauchochorous. Notice the spines, ribs, fur and wax (the blue coloration). The top of a typically adapted plant.
Some plants have fur; sometimes all over the plant, sometimes only near the top. This fur shades the plant even further and is also known to attract water towards the areole. Some plants only have fur near the top. This is very beneficial because the top of the plant is very sensitive to sunlight, new tissues get formed there. Young areoles, with their spines not even wooded yet can get dried up completely in the sun. When an areole is born near the top of the plant, it starts developing spines. At this time the fur appears as well. This fur accompanies the areole as it moves down the plant, shading the growing point inside. By the time the areole is about 15cm away from the top, the fur wears out completely and the now inactive areole gets exposed to the sun.
As for the roots of cacti, they are also fully adapted to living in the desert. Some species (especially plants from very dry deserts) have very shallow root systems that spread very far from the plant. This way the plant can take advantage of tiny amounts of moisture from dew or light rain as the roots spread far away and are very shallow (less than 10cm deep while spreading up to 5 meters from the parent plant). On the other hand, some cacti send their roots deep down (like many Echinocacti) to reach the ground water.
Rainforest cacti often have aerial roots that can collect water all the time when it rains (and it rains very often in South American forests).
The shape of cacti itself is an adaptation. You may have noticed that cacti have a barrel like or candle like shape. This allows for maximum internal volume with a minimum surface area, which is also very smart adaption as a cactus can store a lot of water and have a small external surface area to reduce water loss.
