There might be as many as 10 million species of complex life on this planet today —— a huge number. But add up all of the complex species that ever lived and some biologists think the grand total would be about five billion. The estimate leads to an astonishing conclusion: a staggering 99% of species are not around any more. They have been driven to extinction.
More species are joining the ranks of the extinct every year. Many scientists believe we are living through an episode of remarkably rapid extinction, on a scale that has been seen only five times in the last half a billion years.
They call this current episode the sixth mass extinction —— a large, global decline in a wide variety of species over a relatively short period of time. And they tend to agree that humans are the main cause.
Over-hunting, overfishing, and human-driven habitat loss are pushing many species to the brink. In fact, we have changed the planet so much that some geologists are now suggesting that we have entered a new phase in Earth’s history; an epoch they call the ＂Anthropocene＂. By 2100, it is expected that humans will have caused the extinction of up to half of the world’s current species.
Because we are living through this extinction, it is relatively easy for us to study the driving forces behind it. But how do we determine what caused other mass die-offs that happened long ago? To do so we have to look at what archaeologists, palaeontologists, geologists and other scientists have concluded from the evidence they have gathered.
The trouble is, those scientists do not always agree with one another —— even about the most recent extinction event. As well as the five-or six- mass extinctions, there have also been many smaller extinctions.
One of these mini extinction events happened towards the end of the Pleistocene, a few tens of thousands of years ago. It is sometimes called the ＂megafaunal＂ extinction because many of the species it claimed were particularly large animals, weighing more than 97lb (44kg). However, its cause remains a debate amongst scientists.
1.What can we learn about the sixth mass extinction？
A. Humans are the main cause of it.
B. It means a global decline over a long time.
C. It occurred towards the end of the Pleistocene.
D. Scientists still disagree about the cause of it.
2.What can be inferred from the text about species？
A. 99% of species will not be around any more by 2100.
B. By the 22nd century, there will probably be about five million on this planet.
C. About eight years later we will enter what is called the ＂Anthropocene＂.
D. It is not easy for us to figure out causes behind the＂Anthropocene＂.
3.Which of the following is closest in meaning to the underlined word in the last paragraph ?
A. Land animals. B. Marine life.
C. Huge animals. D. Flesh-eating creatures.
高三英语完形填空困难题
There might be as many as 10 million species of complex life on this planet today —— a huge number. But add up all of the complex species that ever lived and some biologists think the grand total would be about five billion. The estimate leads to an astonishing conclusion: a staggering 99% of species are not around any more. They have been driven to extinction.
More species are joining the ranks of the extinct every year. Many scientists believe we are living through an episode of remarkably rapid extinction, on a scale that has been seen only five times in the last half a billion years.
They call this current episode the sixth mass extinction —— a large, global decline in a wide variety of species over a relatively short period of time. And they tend to agree that humans are the main cause.
Over-hunting, overfishing, and human-driven habitat loss are pushing many species to the brink. In fact, we have changed the planet so much that some geologists are now suggesting that we have entered a new phase in Earth’s history; an epoch they call the ＂Anthropocene＂. By 2100, it is expected that humans will have caused the extinction of up to half of the world’s current species.
Because we are living through this extinction, it is relatively easy for us to study the driving forces behind it. But how do we determine what caused other mass die-offs that happened long ago? To do so we have to look at what archaeologists, palaeontologists, geologists and other scientists have concluded from the evidence they have gathered.
The trouble is, those scientists do not always agree with one another —— even about the most recent extinction event. As well as the five-or six- mass extinctions, there have also been many smaller extinctions.
One of these mini extinction events happened towards the end of the Pleistocene, a few tens of thousands of years ago. It is sometimes called the ＂megafaunal＂ extinction because many of the species it claimed were particularly large animals, weighing more than 97lb (44kg). However, its cause remains a debate amongst scientists.
1.What can we learn about the sixth mass extinction？
A. Humans are the main cause of it.
B. It means a global decline over a long time.
C. It occurred towards the end of the Pleistocene.
D. Scientists still disagree about the cause of it.
2.What can be inferred from the text about species？
A. 99% of species will not be around any more by 2100.
B. By the 22nd century, there will probably be about five million on this planet.
C. About eight years later we will enter what is called the ＂Anthropocene＂.
D. It is not easy for us to figure out causes behind the＂Anthropocene＂.
3.Which of the following is closest in meaning to the underlined word in the last paragraph ?
A. Land animals. B. Marine life.
C. Huge animals. D. Flesh-eating creatures.
高三英语完形填空困难题查看答案及解析
Life is stressful, and complaining may be considered by many as an extension of being________normal.
A. urgently B. absolutely C. casually D. clumsily
高三英语单项填空中等难度题查看答案及解析
1.They talked friendly as if they ______ (be) friends for many years.
2.Tired of the city life, her husband suggested ______ (settle) down in the country after they retired.
3.As one of the most famous tourist ______ (attract), the Great Wall is a symbol of our profound Chinese culture.
4.With his attention ______ (focus) on the computer games, he didn’t notice his mom come in.
5.The novel is said to ______ (translate) into several foreign languages and sells well abroad.
6.I do hope everybody can become the backbone of our nation and make great ______ (contribute) to society.
7.So ______ (challenge) was the task that he had to apply himself to it.
8.______ (struggle) for months 10 find a job since graduation, he finally took a position in a local company.
9.The write couldn’t stand ______ (wake) up by the outside at midnight.
10.The shops have sinned to put ______ Christmas decorations.
高三英语完成句子中等难度题查看答案及解析
Everyone may have a complex and different process of growing up. There are many influential factors in a person’s growth and 1. (发展) of his personality.
As for me, 2. has affected me most in my growth and personality is my family and friends, the two 3. (同等地) important factors. After I was b 4. , my family is the first surroundings. It plays a significant r5. in shaping my character because it’s the most direct source of knowledge and experience for me. As we know, those who are brought 6. in good families tend to have a good character and vice versa. Fortunately, I belong to the 7. (前者). Besides, friends in some ways influence me a lot. Although, we may have many different opinions and personalities, I have really learned something 8. (有益的) from them.
Frankly s 9. , I get lots of valuable things from my family and friends. My family offers me warmth and cares, while my friends give me strength and courage. Therefore, 10. of them have influenced me most in my growth.
高三英语其他题中等难度题查看答案及解析
Everyone may have a complex and different process of growing up．There are many influential factors in a person’s growth and 1. （发展） of his personality．
As for me, 2. has affected me most in my growth and personality is my family and friends, the two 3.（同等地） important factors．After I was b 4. , my family is the first surroundings． It plays a significant r 5. in shaping my character because it’s the most direct source of knowledge and experience for me．As we know, those who are brought 6. in good families tend to have a good character and vice versa．Fortunately, I belong to the 7. （前者）．Besides, friends in some ways influence me a lot．Although, we may have many different opinions and personalities, I have really l 8. something beneficial from them．
Frankly s 9. , I get lots of valuable things from my family and friends．My family offers me warmth and cares, while my friends give me strength and courage．Therefore, 10. of them have influenced me most in my growth．
高三英语其他题中等难度题查看答案及解析
As many as 100 species of fish, some ____ to these waters, may have been affected by the pollution．
| A．relevant | B．immune | C．unique | D．convenient |
高三英语单项填空中等难度题查看答案及解析
--Life ____ be very hard for people living in the north of Canada as it is very
cold there in winter.
—Yes, the weather there _____ be as low as 60℃ below zero.
A.must; can B．shall; must C．will; should D．has to; can
高三英语简单题查看答案及解析
The process of growing up is complex for every person, ________ there are many influential factors in a person's growth as well as the development of his personality.
A．but B．so C．for D．therefore
高三英语单项填空中等难度题查看答案及解析
Many scientists have believed that there may be a _________of life on the Mar．
| A．mark | B．signal | C．sigh | D．sign |
高三英语单项填空简单题查看答案及解析
．In Australia there are over 140 species of snakes, many of ______ are extremely dangerous.
| A．which | B．that | C．them | D．those |
高三英语单项填空简单题查看答案及解析