Many of the earth’s plants and animals have a...

Many of the earth’s plants and animals have already ______ and several other species are endangered．

A．died away           B．died out       C．died down     D．died of

高三英语单项填空中等难度题查看答案及解析

Many of the earth’s plants and animals have already1.(die) out, and a hundred species become 2.(endanger) every day. If nothing is done, we may find ourselves3. (lonely) on the earth.

Wild animals live in the4. (forest) which are being destroyed by people. As5. result, the animals are　 6.(lose) their habitats. Without the trees, the animals are short of food. And many animals are dying out because of pollution.

I suggest that measures should be taken　 7.(protect) wildlife. The government should keep people 8.destroying forests and shut down the factories 9.　 pollute rivers and air, I think more wildlife reserves should also be 10.(build)

高三英语语法填空中等难度题查看答案及解析

Vast parts of Earth should be left wild

To avoid mass extinctions of plants and animals， governments should protect a third of the oceans and land by 2030 and half by 2050， with a focus on areas of high biodiversity． So say leading biologists in an editorial in the journal Science．

This isn't just about saving biodiverse areas， says Jonathan Baillie of the National Geographic Society，one of the authors． It is also about saving ourselves by protecting_____ natural systems， or ecosystems，and their benefits to us， known as ecosystem services． "We are learning that the large areas that remain are important for providing services for all life． The forests， for example， are_____ for absorbing and storing carbon，" says Baillie．

At present， just 3.6 per cent of the planet's oceans and 14.7 per cent of land is protected by law． At the 2010 Nagoya Conference of the Convention on Biological Diversity， governments agreed to protect 10 per cent of the oceans and 17 per cent of land by 2020．

But this isn't nearly enough， says Baillie． In the editorial， he and his coauthor， Ya﹣Ping Zhang of the Chinese Academy of Sciences， want governments to set much bigger_____ at the next major conference on biodiversity in 2020．

"We have to enormously_____ our ambition if we want to avoid an extinction crisis and if we want to maintain the ecosystem services that we_____ benefit from，" says Baillie． "The trends are in a_____direction， it's just we have to move much faster．"

It is hard to work out how much space is needed to preserve biodiversity and ecosystem_____， the pair say， because there is so much we don't know about life on Earth ﹣ like how many species there are．

_____，　 most estimates suggest that between 25 and 75 percent of high biodiversity regions or major ecosystems should be protected．Therefore，we， including governments，should be_____　 when setting goals and strategies．

"There is no doubt that we need far more land and sea_____ for conserving and retaining nature，"says James Watson at the University of Queensland in Australia． "Targets like 50 per cent are in the right ball park when it comes to the minimal_____ of area needed to conserve biodiversity．"

But Watson and others stress that which areas get protected is even more important than the overall percentage． "The key thing is to protect the right areas，" says Jose Montoya of the Station for Theoretical and Experimental Ecology in Moulis， France． "If we_____ protect a proportion of the territory，governments will likely protect what's easy， and that's usually areas of_____ biodiversity and ecosystem service provision．"

In fact， a third of the 3.6 percent of land that is already meant to be protected is actually being_____，Watson's team reported last month． So only_____ areas to be protected isn't enough．

1.A. stricter　　 B. wider　　 C. safer　　 D. simpler

2.A. unique　　 B. sufficient　　 C. critical　　 D. fit

3.A. examples　　 B. values　　 C. awards　　 D. objectives

4.A. increase　　 B. achieve　　 C. lack　　 D. frustrate

5.A. barely　　 B. currently　　 C. roughly　　 D. thoroughly

6.A. opposite　　 B. fixed　　 C. complex　　 D. positive

7.A. approaches　　 B. management　　 C. benefits　　 D. degradation

8.A. Therefore　　 B. Furthermore　　 C. However　　 D. Otherwise

9.A. concerned　　 B. changeable　　 C. firm　　 D. cautious

10.A. deserted　　 B. secured　　 C. measured　　 D. distributed

11.A. damage　　 B. cost　　 C. amount　　 D. standard

12.A. completely　　 B. merely　　 C. virtually　　 D. desperately

13.A. mass　　 B. tropical　　 C. marine　　 D. low

14.A. exploited　　 B. expanded　　 C. restored　　 D. discovered

15.A. developing　　 B. covering　　 C. declaring　　 D. utilizing

高三英语完形填空中等难度题查看答案及解析

Many of us have wondered what Earth is like beneath the surface. So have writers and scientists. In French novelist Jules Verne’s masterpiece Journey to the Center of the Earth, explorers go down to Earth’s center and discover amazing wonders.

But in real life, human beings haven’t even come close to the planet’s core (核心). The core is over 6,000 km down. The deepest hole ever created, according to the BBC, is the Kola Superdeep Borehole in Russia, which only goes 12.3 km down.

So how do we know about everything down below without any samples？

One good way to start is to think about the Earth’s density (密度), Simon Redfern of the University of Cambridge in the UK told the BBC.

“The density of the material on Earth’s surface is much lower than the average density of the whole Earth, so that tells us there’s something that has greater density,” Redfern said.

The challenge is to find out which heavy materials the core is made of. And the main material scientists have found is iron. The idea is that when Earth formed 4.5 billion years ago, a lot of iron made its way down to the core, taking up about 80 percent of it. Today scientists are still working on finding out which other materials the core could be made up of.

You might also wonder how we know the size of the core. There’s a one-word answer: seismology (地震学).

When an earthquake happens, seismic stations around the world record the shockwaves it sends throughout the planet. It’s like hitting one side of the planet with a huge hammer and listening on the other side for the noise.

Early research found that some shockwaves, called “S-waves”, went missing. S-waves can only travel through solid material, but not through liquid, so they must have found something molten in Earth’s center. By following the S-waves’ paths, scientists found out that rocks became liquid around 3,000 km down.

There are still many questions about the Earth’s core to answer. But the study of the dark world below isn’t just for scientists’ curiosity.

The movement of Earth’s molten iron core builds up a powerful magnetic (有磁力的) field. It protects us from radiation from the sun and is needed for compasses and GPS systems to work.

So perhaps none of us will ever set eyes on the core, but it’s good to know it’s there.

1.The author mentions Jules Verne’s novel Journey to the Center of the Earth in the first paragraph to　　　　　　　　 .

A. discuss the possibility of going down to Earth’s center

B. show how much humans have discovered about Earth

C. paint a picture in our imagination of the dark world below

D. show humans’ deep interest in Earth’s center

2.We can learn from the article that “S-waves”　　　　　　　　　　　　 .

A. are often used to predict earthquakes

B. cannot travel through liquid material

C. are the most noticeable shockwaves produced by earthquakes

D. can travel most rapidly at 3,000 kilometers below Earth’s surface

3.We can infer from the last three paragraphs that 　　　　　　　　　　　 .

A. research into Earth’s core has hardly made any progress in recent years

B. improvements in GPS systems could help people find out more about Earth

C. Earth’s core helps to protect humans from harm

D. scientists are likely to reach Earth’s center within dozens of years

高三英语阅读理解中等难度题查看答案及解析

Today, many species of animals and plants are endangered. This means they are in danger of becoming extinct and living on only in the pages of history books. The famous dodo is a classic example of a creature that became extinct. A flightless bird that lived on the island of Mauritius, it was discovered by sailors in 1598 but was hunted to extinction by 1681.

Hunting has caused the Bengal tiger and the African elephant to be endangered today but habitat destruction can also lead to extinction. This is equally true for plants. Animals and plants disappear for other reasons too, but the main cause is often a disruption（打乱，破坏） in the natural food chain, whether due to hunting, habitat destruction, or even the introduction of alien species.

The natural food chain is the cycle that governs the existence of all life on this planet. It is a carefully balanced cycle and any imbalance that occurs can cause knock-on effects that have serious consequences. At the beginning of the natural food chain are plants which turn sunlight into energy and draw nutrients from the earth. Plants are called producers.

After the producers come the consumers. There are three tiers of consumers. First are creatures such as plant-eating animals, fish and insects which feed off the producers. These animals that only eat plants are called herbivores. The second tier of consumers are carnivores - animals that live off other animals. The third tier of consumers eats both other animals and plants. These consumers, including most humans, are called omnivores.

After animals and plants die, they become food for other smaller creatures, such as bacteria and some plants, such as fungi. As they feed, these creatures turn the dead bodies back into gases and minerals which are again food for the producers at the beginning of the food chain. And so the cycle continues.

All of nature is connected and governed by hundreds of these delicate food chains and if a single plant in the chain cannot survive, then the insects that live off the plant start to die and the animals that eat the insects also start to die.

When a food chain is disrupted, the consequences can be extremely serious. One estimate suggests that for each plant species that is lost, up to 30 animals and insects may also die out. One wonders how many species were affected by the extinction of the dodo?

Humans can have disastrous effects on food chains. We've already mentioned hunting but now let's look at travel. When people first started to explore the world they took plant and animal species from their home countries and introduced them wherever they went. They didn't realize that by introducing alien species they were disrupting the natural food chains of the areas they discovered. Although there are strict rules in place today controlling the import and export of alien species, some places are still fighting the effects of aliens introduced hundreds of years ago.

For example, Gough Island in the South Atlantic Ocean is a breeding ground for albatrosses that have been nesting there for centuries. But in the 19th century, mice from passing ships were brought to the island. Being a species alien to the island, they had no natural predators and have now grown to such a size that they are attacking and killing albatross chicks. If they are allowed to continue, they will wipe out the albatross population.

With import laws and people's rising awareness of how humans affect the natural environment, hopefully we can learn to fit better into the natural food chains that govern our world. Otherwise we need to accept that the loss of any more plants and animals could eventually mean our own extinction.

1.What do the first two paragraphs mainly tell us?

A. Hunting and habitat destruction lead to extinction.

B. Many species of animals and plants are endangered.

C. Plants and animals become extinct for the same reasons.

D. The main cause of extinction is often a disruption in the natural food chain.

2.Which of the following sentence is TRUE according to the passage?

A. Strict rules alone can remove the bad effects of alien species.

B. Plants, herbivores and carnivores are the three tiers of consumers.

C. If a bird becomes extinct, the relevant food chain will be disrupted.

D. Animals and plants become extinct because alien species are imported.

3.By mentioning the mice in Gough Island, the author intends to highlight ______.

A. mice worldwide are growing all the time

B. being aliens, they had no natural predators

C. some places are still fighting the effects of aliens

D. traveling can have disastrous effects on food chains

4.What is the best title of the passage?

A. Survival of the fittest.

B. Endangered animals and plants.

C. How to protect the natural environment.

D. The link between food chains and extinction.

高三英语阅读理解中等难度题查看答案及解析

Many animals  31         (disappear) during the history of the earth.       32          (famous) of these animals were dinosaurs. They lived on the earth        33           (ten) of millions of years ago, long    34        humans came into being. There were many different species of dinosaur and several of them have been found in China. The eggs of twenty-five species have been found in Xixia County, Nanyang, Henan Province, and not long ago a rare new species of bird-like dinosaur was discovered in Chaoyang County, Liaoning Province. The scientists were surprised      35         (find) they could run    36      other dinosaurs, but also climb trees. They could tell this from the way the bones   37          (join) together.

Dinosaurs died    38        quickly about 65 million years ago. Some scientists think it was after a large rock hit the earth and put too much dust into the air. Others think the earth got    39        hot for the dinosaurs to live on any more. Nobody knows   40          sure. In the same way there are animals that have died out more recently and no one knows why. Listen to the story about the dodo, an animal that has disappeared from the earth.

高三英语填空题简单题查看答案及解析

_____from other continents for millions of years, Australia has many plants and animals not found in any other country in the world.

A. Being separated                   B. Having separated

c. Having been separated                 D. To be separated

高三英语单项填空中等难度题查看答案及解析

_________ from other continents for millions of years, Australia has many plants and animals not found in any other country in the world.

高三英语单项填空困难题查看答案及解析

The conservation area is very important for preserving many animals and plants, which would ______ run the risk of becoming extinct.

A. otherwise               B. therefore                         C. though                              D. instead

高三英语单项填空中等难度题查看答案及解析

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（海绵动物）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（内脏）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."

1.The underlined word "facilitated" in Para. 3 is closest in meaning to＿＿．

A. prevented B. promoted C. interrupted D. witnessed

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

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

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．analyze how atmospheric oxygen stepped up the evolution of oceanic animals

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

高三英语阅读理解中等难度题查看答案及解析