The evolution of the first animals may have oxygenated（供氧）Earth's oceans. New research
led by the University of Exeter challenges the long held belief that oxygenation of the atmosphere and oceans was a precondition for the evolution of complex life forms.
The study, published in the journal Nature Geoscience, builds on the recent work of scientists in Denmark who found that sponges（海綿動(dòng)物）一the first animals to evolve一require only small amounts of oxygen.
Professor Tim Lenton of the University of Exeter, who led the new study, said: "We argue that the evolution of the first animals could have played a key role in the widespread oxygenation of the deep oceans. This in turn may have facilitated the evolution of more complex, mobile animals."
Critical to determining oxygen levels in the deep ocean is the balance of oxygen supply and demand. Demand for oxygen is created by the sinking of dead organic material into the deep ocean. The new study argues that the first animals reduced this supply of organic matter一both directly and indirectly.
Sponges feed by pumping water through their bodies, "digesting" the tiny particles of organic matter, and thus helping oxygenate the shelf seas that they live in. By oxygenating more of the bottom waters, the first animals actually increased the removal of the essential nutrient phosphorus（磷）in the ocean. This in turn reduced the productivity of the whole ocean ecosystem, lowering oxygen demand and thus oxygenating the deep ocean.
A more oxygen-rich ocean created ideal conditions for more complex mobile animals to evolve, because they have a higher requirement for oxygen. These included the first predatory（肉食的）animals with guts（內(nèi)臟）that started to eat one another, marking the beginning of the type of food webs we are familiar with today.
Professor Simon Poulton of the University of Leeds, who is a co-author of the study, added: "This study provides a possible mechanism for ocean oxygenation without the requirement for a rise in atmospheric oxygen. It therefore questions whether the long-standing belief that there was a major rise in atmospheric oxygen at this time is correct. We simply don't know the answer to this at present, which is ultimately key to understanding how our planet evolved to its current habitable state. Geochemists need to come up with new ways to explain oxygen levels on the early Earth."
【小題1】The underlined word "facilitated" in Para. 3 is closest in meaning to＿＿．

A．prevented

B．promoted

C．interrupted

D．witnessed

【小題2】From paragraphs 4 to 6, we can infer that＿＿．

A．phosphorus can keep the productivity of the ocean ecosystem

B．complex animals consume the same amount of oxygen as sponges

C．the sinking of dead organic material into the deep ocean produces oxygen

D．the existence of the first animals marks the beginning of modern food webs

【小題3】 From the last paragraph, we can learn Pro. Simon Poulton believes that＿＿．

A．their study gives a new explanation for the high oxygen content in the air

B．oxygen increased greatly in the air as the first animals oxygenated the oceans

C．their study answers the question of how the earth evolved to the present state

D．ocean oxygenation does not necessarily require a rise in atmospheric oxygen

【小題4】The main purpose of the passage is to＿＿．

A．present the view that the first animals played an active role in oxygenating oceans

B．introduce two opposite opinions on how the first animals oxygenated oceans

C．a(chǎn)nalyze how atmospheric oxygen stepped up the evolution of oceanic animals

D．explain how oceanic oxygen determines the amount of atmospheric oxygen

It is a tall tale that terrifies most young children. Swallow a piece of chewing gum and it will remain in your body for seven years before it is digested. An even worse tale is that swallowed gum can wrap itself around your heart.
But what does happen if you should accidentally eat a stick of gum? Chewing gum is made out of gum base, sweeteners, coloring and flavoring. The gum base is pretty indigestible一it is a mixture of different ingredients that our body can’t absorb.
Most of the time, your stomach really cannot break down the gum the way it would break down other foods. However, your digestive system has another way to deal with things you swallow. After all, we eat lots of things that we are unable to fully digest. They keep moving along until they make it all the way through the gut and come out at the other end one or two days later.
The saliva in our mouths will make an attempt at digesting chewing gum as soon as we put it in our mouths. It might get through the shell but many of gum’s base ingredients are indigestible. It’s then down to our stomach muscles一which contract and relax, much like the way an earthworm moves一 to slowly force the things that we swallow through our systems.
Swallowing a huge piece of gum or swallowing many small pieces of gum in a short time can cause a blockage within the digestive system, most often in children, who have a thinner digestive tube than adults 一but this is extremely rare.
【小題1】Children might feel terrified after swallowing chewing gum mainly because        .

A．they believe the tall tales about chewing gum

B．chewing gum will stay in their body for years

C．their heart will be wrapped by chewing gum

D．chewing gum is indigestible for children

【小題2】What happens to the food that can’t be fully broken down?

A．It remains in our digestive system forever.

B．It will be eventually moved out of our body.

C．It will fight against the power of the gut.

D．It will stick to the gut for one or two days.

【小題3】What would be the best title for text?

A．How does our digestive system work?

B．Can chewing gum be swallowed by kids?

C．Does swallowing chewing gum matter?

D．Why swallowing chewing gum frightens kids?

Air pollution is a leading cause of cancer and classified among top human carcinogens (致癌物質(zhì)), said the International Agency for Research on Cancer (IARC), which is the World Health Organization's (WHO) cancer agency, on Oct 17,2013.“Our task was to evaluate the air everyone breathes rather than focus on specific air pollutants,” the IARC's Dana Loomis said in a statement. “The results from the reviewed studies point in the same direction the risk of developing lung cancer is significantly increased in people exposed to air pollution.”
In 2010, lung cancer resulting from air pollution killed 223,000 people worldwide, and there was also convincing evidence that it increases the risk of bladder (膀胱) cancer. Loomis said people in Asia, Eastern North America, some places in Central America and Mexico, as well as North Africa have relatively high exposure(暴露). Developing countries with large populations and booming manufacturing sectors, such as China, are particularly at risk. This week, Harbin, the capital city of Heilongjiang province, became the first Chinese city to officially suspend classes due to serious smog, really good for teachers and students.
Many developed countries face similar problems, although to a lesser（較少的、次要的） degree than most developing nations. Between 91 and 96 percent of Europeans living in cities are exposed to levels of PM2.5—tiny particles with a diameter of less than 2.5 micrometers—that are higher than the WHO safety limits.
Although both the composition and levels of air pollution can vary dramatically from one location to the other, the IARC said its conclusions apply to all areas of the world. “Given the scale of the exposure affecting people worldwide, this report should send a strong signal to the international community to take action without further delay,” said Christopher Wild, director of the IARC.
【小題1】What’s the main task of IARC?

A．To focus on cancer-causing substances.

B．To evaluate the air quality.

C．To study the developing risk of cancer.

D．To send signals to the international community.

【小題2】The underlined word “suspend” in Paragraph 2 probably means ______.

A．a(chǎn)ccelerate	B．a(chǎn)cknowledge
C．delay	D．decline

【小題3】Why should the international community take action without further delay?

A．A large number of people worldwide are exposed to air pollution.

B．More and more people in developing countries are exposed to air pollution.

C．Developed countries face air pollution, the level of which is higher than the safety limits.

D．The composition and levels of air pollution vary from place to place.

【小題4】What might be the best title of the passage?

A．PM2.5，bad effect.

B．Safety limits of air pollution.

C．Signals of air pollution.

D．Air pollution, cancer risk.

Sea Life Melbourne Aquarium (水族館)
The all-new Sea Life Melbourne Aquarium, located in the heart of Melbourne’s CBD, is one of Victoria’s leading visitor attractions and an unforgettable outing for the whole family. Having 12 amazing zones of discovery, Sea Life Melbourne Aquarium is the very place that you cannot miss when you visit the city.
* Opening Times
Sea Life Melbourne Aquarium is open from 9:30 am until 6:00 pm every day of the year, including public holidays. Last admission is at 5:00 pm, one hour before closing.
* Location.
Sea Life Melbourne Aquarium is located on the corner of Flinders Street and King Street, Melbourne. It is located on the Yarra River, opposite Crown Entertainment Complex.
* Getting to Sea Life Melbourne Aquarium
Train
The Sea Life Melbourne Aquarium train stop is located on the free City Circle Tram route (公交線路) and also routes 70 and 75. City Circle trams run every 10 minutes in both directions.
Shuttle Bus
The Sea Life Melbourne Aquarium is a free bus service, stopping at key tourist attractions in and around the City. Running daily, every 15 minutes from 10:00 am to 4:00 pm.
Car Parking
While there is no public car parking at Sea Life Melbourne Aquarium, there are several public car parking lots available only a short walk away.
* Wheelchair Access
Sea Life Melbourne Aquarium provides people in wheelchairs with full access to all 12 zones. Each floor also has wheelchair accessible toilets.
* Terms
Tickets will be emailed to you immediately after buying or you can download and print your ticket once payment has been accepted. Please print out all tickets bought and present at the front entrance of Sea Life Melbourne Aquarium. No ticket, no entry!
【小題1】Sea Life Melbourne Aquarium _________ .

A．is located at the center of the CBD in the city

B．has 12 most attractive places in Melbourne

C．a(chǎn)dmits visitors from 9:30 am until 6:00 pm

D．is beside Crown Entertainment Complex

【小題2】Getting to Sea Life Melbourne Aquarium, visitors can take ________.

A．trains from southern Cross train station

B．shuttle buses around the train station

C．boats across the Yarra River

D．either tram route 70 or 75

【小題3】Sea Life Melbourne Aquarium offers visitors ________.

A．free car parking	B．wheelchair access
C．Internet connection	D．transportation service

【小題4】Tickets to Sea Life Melbourne Aquarium ________ .

A．a(chǎn)re free to all visitors

B．can be bought by email

C．a(chǎn)re checked at the entrance

D．can be printed at the ticket office

A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.
“It’s extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components. “The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.
They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it’s connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.
While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers’ fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.
Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”
【小題1】The robotic fly project has been conducted __________.

A．just by accident

B．within a decade

C．just by a professor

D．for more than ten years

【小題2】The difficulty the team of engineers met with while making the robotic fly was that __________.

A．they had no model in their mind

B．they did not have sufficient time

C．they had no ready-made components

D．they could not assemble the components

【小題3】Which of the following can be learned from the passage?

A．The robotic flyer is designed to learn about insects.

B．Animals are not allowed in biological experiments.

C．There used to be few ways to study how insects fly.

D．Wood’s design can replace animals in some experiments.

【小題4】Which of the following might be the best title of the passage?

A．Father of Robotic Fly

B．Inspiration from Engineering Science

C．Robotic Fly Imitates Real Life Insect

D．Harvard Breaks Through in Insect Study

Google is testing its newest high-tech device, Google Glass. Most of the technologies for Google Glass are already available on smart phones. Google has taken those same technologies and added them to eyeglass frames（眼鏡架）. The company describes the glasses as wearable computers that would change the way people view others and the world.
"Google Glass is a tiny computer that sits in a lightweight frame, and rests neatly above your eye and it makes exploring and sharing the world around you a lot easier,” said Chris Dale, the Senior Manager of Communications for Google Glass.
The glasses have a tiny video screen and a camera that connect wirelessly to the Internet through WIFI, a smartphone, or a tablet computer. You can make and receive calls, send and receive texts, take pictures, record video or search the web. You control Google Glass using your voice, and a touchpad on the right arm of the frame.
Professor Marcia Dawkins is among a select group of people who have been given a chance to test out Google Glass. "I thought this is something I definitely need for my classroom and hopefully for my personal life too."
The Professor's Google Glass looks like a pair bright orange glasses, without the actual glass. But there's a tiny rectangular（長方形的）glass at the top right-hand corner. Through that glass, she has been recording video while biking. She also has been able to talk to her sister in Thailand, and she plans to use the device to teach a public speaking class.
But not everyone is excited about Google Glass. Some are concerned about possible risks to privacy.
John Simpson is the director of the privacy project at Consumer Watchdog.
"It is going to allow people to come in and spy on you and record that, without you knowing what is going on."
Filmmaker Chris Barrett showed just how easy it is to record people without them knowing it. His glass captured（捕捉）a man getting arrested after a fight. He shared the video on You Tube.
Also some are concerned about the use of facial recognition（面部識(shí)別）technology on Google Glass. But Google says it will not approve the use of such applications. The Internet company says it is still testing its new device, and it hopes to make Google Glass available to the public by early next year.
【小題1】The technologies Google has made use of for Google Glass are______.

A．completely new

B．mostly already in use for smartphones

C．high-tech but out-of-date

D．a(chǎn)ll old

【小題2】Which of the following is not true about Google Glass?

A．It’s a very small computer.

B．It’s very light in weight.

C．Everyone can buy it now.

D．It can be used for teaching by school teachers.

【小題3】While cycling, the Professor has used the Glass to ______.

A．record video and chat	B．send emails
C．teach a class	D．spy on others

【小題4】What can be inferred from the passage？

A．Google has done what it can to protect people’s privacy.

B．Google Glass may be used for bad purposes.

C．Most people feel worried about the use of the Glass.

D．Google Glass is more useful than smartphones.

One of the most important recent medical breakthroughs has been the impact of gut flora（腸道菌群）on overall health. This dynamic mix of bacteria in the digestive tract（消化道）may affect everything from obesity to asthma（哮喘）．
The Gut-Mood Link
Anyone who's ever experienced "butterflies" in his or her stomach knows that the gut and the brain are connected. But until recently, scientists hadn't realized that the trillions of bacteria in our digestive tract may be driving the relationship.
One recent experiment suggests that you can control calm. Canadian researchers gave healthy mice a mixture of antibiotics, which change the makeup of GI-tract（胃腸道）bacteria. Over two weeks, some animals became more anxious and some less, depending on which drugs they received. In another study, when gut bacteria from calm mice were transferred to anxious mice, the jittery（緊張的）creatures seemed less nervous.
UCLA professor Kirsten Tillisch, doctor of medicine, recently had healthy women eat a yogurt
rich in certain types of "good" probiotic（益生菌的）bacteria. Two 'Control groups ate yogurt without such bacteria or ate nothing. Brain scans of the probiotic-yogurt eaters indicated changes in regions that could be associated with a less-anxious response in fearful or stressful situations compared with the control groups.
Scientists are even exploring whether gut microbes（微生物）might treat some brain disorders. A new study in Cell found that mice with features of autism（自ICJ癥）given a type of bacteria in healthy human GI tracts exhibited less autism-like behavior. In a recent case report, a Boston ps. chiatrist says a course of certain probiotics and antibiotics helped relieve a patient's compulsive disorder.  -We tend to focus on how your mood affects your body from the top down, not the bottom up,"  says Dr. Tillisch. "Now we know that the gut affects how your brain responds to the environment- it's a remarkable change in thinking.”
How Bacteria Talk to the Brain Scientists aren't sure how gut flora affect brain chemistry. One theory is that the bacteria access pathways along the nerve, the main highway in the nervous system that links the brain to the gut.  Another is that the bacteria influence the immune system, releasing chemicals that affect conditions like depression. Finally, researchers believe that bacteria produce or affect the metabolism（新陳代瀉'i) of chemicals, which change brain function.
Dr. Tillisch told me that patients always ask which probiotics will lift their mood．Her answer:
"We don't know yet, but we hope to one day." In the future, patients might receive probiotics or transplant（移植） in which bacteria from the gut of a healthy person are transferred to the gut of a sic': one-to prevent or treat mental health issues. But these approaches are years away from primary time．Until then, a diet rich in fruit and veggies helps cultivate（培養(yǎng)）better-balanced microbes than a typical Western diet high in animal and processed products. Avoiding unnecessary antibiotics, particularly in early childhood, may also establish healthier gut bacteria.
【小題1】 According to the passage, gut bacteria might help us in many ways EXCEPT＿_(dá)．

A．lightening our mood	B．treating autism
C．relieving depression	D．transplanting gut flora

【小題2】The missing sentence "Everyday foods may also affect the composition of gut bacteria, and in
turn, brain chemistry." could be put before＿_(dá)·

A．Paragraph 2	B．Paragraph 3
C．Paragraph 4	D．Paragraph 5

【小題3】Which of the following can be the best subtitle for the last paragraph?

A．Cultivating a Happier Gut

B．Growing Bacteria in the Future

C．Balancing Microbes and Diet

D．Living a Happy Healthy Life

Most people know precious gemstones (寶石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.
Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (線索) to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.
Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.
To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.
The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.
In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.
Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.
【小題1】We learn from Paragraph 1 that __________.

A．a(chǎn)n emerald and a ruby are names of diamonds.

B．it’s not difficult to tell where the gem was mined.

C．a(chǎn)ppearances help to identify the origin of gemstones.

D．diamonds from different places may appear the same.

【小題2】Why did the U.S. government pass law that requires companies selling gemstones to  determine the origins of their stones?

A．To look for more gemstones.

B．To encourage violent civil wars.

C．To reduce the trade in blood minerals.

D．To develop the economy.

【小題3】Which of the following facts most probably helps McManus and her team in identifying the origin of stones?

A．Heat can turn ice into water or water into steam.

B．Gemstones from the same area produce similar light patterns.

C．Laser can change a miniscule part of the gemstone into plasma.

D．Materialytics has already collected patterns from thousands of gemstones.

【小題4】From the last two paragraphs, what can be inferred about the laser technique?

A．It is ready for commercial use.

B．People can use the new tool to find more gemstones.

C．It can significantly reduce the gemstones trade in blood minerals.

D．It will bring about a revolutionary change in identifying the origin of minerals.

【小題5】The author wrote this passage mainly to __________.

A．tell us how to identify the origin of diamonds.

B．introduce a laser technique in identifying a stone’s origin

C．prove identifying the origin of gemstones are difficult

D．a(chǎn)ttract our attention to reducing trade in blood minerals

While most people consider that laughter is one of the nature’s great treatments for a whole range of mental and physical diseases, it is still a serious scientific subject that researchers are trying to figure out.
“Laughter is social.” says Robert R. Provine, author of the book “Laughter: A Scientific Investigation”, who has been studying laughter for decades. “Almost all people laugh ‘ha-ha-ha’ basically the same way. Whether you speak Mandarin, French or English, everyone will understand laughter. There is a pattern generator(發(fā)生器) in our brain that produces this sound.
Laughing is also a good way of communicating. Babies laugh long before they speak. No one teaches them how to laugh. They just do it. People may laugh at a prank(惡作劇) on April Fools’ day. But surprisingly, only 10 to 15 percent of laughter is the result of someone making a joke. Laughter is mostly about social responses rather than reaction to a joke. Deaf people laugh without hearing and people on cell phones laugh without seeing, which shows that laughter isn’t dependent on a single sense but on social interactions.
And laughter is not just a human thing. Chimps tickle(撓癢) each other and even laugh when another chimp pretends to tickle them.
Jaak Panksepp studies rats that laugh when he tickles them. It turns out rats love to be tickled. They return again and again to the hands of researchers tickling them, Panksepp’s video shows.
By studying rats, scientists can figure out what’s going on in the brain during laughter. It has been found that laughter in rats produces a chemical that acts as an antidepressant(抗抑郁藥) and anxiety-reducer. Scientists think the same thing probably happens in humans, too. This would give doctors a new chemical target in the brain in their effort to develop drugs that fight depression and anxiety in people.
Even so, laughter itself has not been proved to be the best medicine, experts said. “No study has shown that laughter produces a direct health benefit,” Provine said, “l(fā)argely because it’s hard to separate laughter from just feeling good.”
【小題1】 Why does the writer say “l(fā)aughter is mostly about social responses rather than reaction to a joke”?

A．because people can communicate with each other by laughing.

B．because laughter is the same sound in all the human’s languages.

C．because laughter is considered a basic language all people can learn.

D．because everyone can understand the meaning of the word laughter.

【小題2】From the last two paragraphs we know that______.

A．laughter has no direct connection with good feelings

B．laughing every day can cure people of many diseases

C．the medical functions of laughter are still under experiment

D．scientists have learned what is happening in a human brain when he laughs

【小題3】 Which of the following statements is true according to the passage?

A．Laughter depends on many senses.

B．Laughter is a social response shared by all creatures.

C．If you speak different languages, you will laugh differently.

D．A new medicine has been developed based on the laughter research.

A rainforest is an area covered by tall trees with the total high rainfall spreading quite equally through the year and the temperature rarely dipping below 16℃.Rainforests have a great effect on the world environment because they can take in heat from the sun and adjust the climate.Without the forest cover，these areas would reflect more heat into the atmosphere，warming the rest of the world.Losing the rainforests may also influence wind and rainfall patterns，potentially causing certain natural disasters all over the world.
In the past hundred years，humans have begun destroying rainforests in search of three major resources(資源)：land for crops，wood for paper and other products，land for raising farm animals.This action affects the environment as a whole.For example，a lot of carbon dioxide(二氧化碳)in the air comes from burning the rainforests.People obviously have a need for the resources we gain from cutting trees but we will suffer much more than we will benefit.
There are two main reasons for this.Firstly，when people cut down trees，generally they can only use the land for a year or two.Secondly，cutting large sections of rainforests may provide a good supply of wood right now，but in the long run it actually reduces the world's wood supply.
Rainforests are often called the world's drug store.More than 25% of the medicines we use today come from plants in rainforests.However，fewer than 1%of rainforest plants have been examined for their medical value.It is extremely likely that our best chance to cure diseases lies somewhere in the world's shrinking rainforests.
【小題1】Rainforests can help to adjust the climate because they ______.

A．reflect more heat into the atmosphere

B．reduce the effect of heat from the sun on the earth

C．bring about high rainfall throughout the world

D．rarely cause the temperature to drop lower than 16℃

【小題2】What does the word“this”underlined in the third paragraph refer to?

A．Humans have begun destroying rainforests.

B．People have a strong desire for resources.

C．We will lose much more than we can gain.

D．Much carbon dioxide comes from burning rainforests.

【小題3】It can be inferred from the text that ______.

A．we can get enough resources without rainforests

B．we will grow fewer kinds of crops in the gained land

C．the level of annual rainfall affects wind patterns

D．there is great medicine potential in rainforests

【小題4】What might be the best title for the text?

A．Rainforests and the Environment

B．How to Save Rainforests

C．How to Protect Nature

D．Rainforests and Medical Development