【推荐2】A team of scientists have studied thousands of species of birds to understand why there is so much diversity in the length of time they take to grow from a fertilized (受精的) egg into an independent adult. The study, published in Nature Communications, is the first one to consider the importance of lifestyle and environmental factors alongside evolutionary history and body size to explain the variation.

All organisms face a trade-off (交换) between reproducing and surviving and they solve this problem in different ways. The team found that migratory birds develop much quicker, which may ensure they are ready to return to their winter habitats at the end of each summer. Findings showed that birds that breed and live in safer environments with fewer predators typically took longer to develop, possibly because they can afford to spend longer since there is no danger or need to leave. They also found that bird species with a “live fast die young” strategy develop quicker, allowing them to maximize the number of offspring (后代) they can produce in the short time available. As expected, the research showed that bigger birds took longer to develop — but even among birds of a similar size there was variation in development times.

Dr. Chris Cooney, from the University of Sheffield’s Department of Animal and Plant Sciences and lead author of the research, said, “The amount of time it takes for a fertilized egg to develop into a fully grown adult varies hugely across the animal kingdom. For instance, it takes an elephant almost 10 years to reach independence, whereas a fruit fly is fully grown after only a matter of days. This extraordinary diversity is also prevalent within birds, where albatrosses (信天翁) can take almost a year to develop from an embryo (胚胎) to an independent adult, but a typical UK garden songbird (鸣禽) takes little more than a month. We found that certain aspects of a species’ lifestyle and environment are important in explaining how long they take to develop.”

The study on birds gives scientists some clues about the type of factors that may be important in other species. However, it may be that different factors are important for determining development length in other animal groups. Therefore, the next step is to address these questions using data that covers the whole scale of the animal kingdom — from fish to mammals to insects — to gain an even broader insight into the factors shaping these fundamental differences across species.

1. What does the study mainly focus on?

A．The number of bird species.	B．The changes of bird habitats.
C．The development length of birds.	D．The life span of birds.

2. What does the underlined word “prevalent” in paragraph 3 probably mean?

A．Rare.

B．Common.

C．Special.

D．Strange.

3. What can we know from Dr. Chris Cooney’s words?

A．The development times vary with the species.

B．Size determines the speed of birds’ development.

C．Animals living in the same place develop at the same rate.

D．Bigger animals always grow more slowly than smaller ones.

4. Why will scientists use data covering the whole scale of the animal kingdom?

A．To study the cause of the species diversity.

B．To show the basic differences among species.

C．To explore the evolutionary history of animals.

D．To figure out other factors in development length.

【推荐3】Dogs in the classroom lower stress of primary school students, new research has found. The study by UK researchers found spending some time with a dog twice a week was better for reducing stress on students than many other classroom relaxation activities. And the benefits of these “dog dates” were similar for children in both normal and special schools.

Stress is known to negatively influence a child’s learning, behaviour, health and mood. This has led schools to try a number of ways to reduce stress, including yoga, mindfulness, physical activities and even having animals in classrooms.

The researchers from the University of Lincoln measured students’ stress levels by tracking the level of the stress in their saliva (唾液). They studied 105 students aged 8 to 9 in four normal schools as well as 44 children of a similar age in seven special schools in the UK. The children were divided into three groups: a group that spent time with a dog; a group that spent time doing relaxation activities; and a “control” group that did neither of these things. Students in the dog group spent 20 minutes with a trained dog twice a week for four weeks. The relaxation group spent the same amount of time doing exercises.

The researchers found that the children in the dog group had “extremely lower” stress levels, while those in the relaxation and control groups recorded an increase over the school term. The study, which was published in the journal PLOS ONE, also found stress was lowest in the children in the dog group immediately after their contact with the puppies. “Dog-assisted activities can lead to lower stress levels in schoolchildren with and without special educational needs,” University of Lincoln researcher Kerstin Meints said, “but more research is needed to discover what was the ideal amount of time and contact with dogs for the best effect.”

1. What is the benefit of having dogs in the classroom according to the research?

A．Lower stress for students.

B．Making students less lonely.

C．Building up students’ health.

D．Improving students’ confidence.

2. How did the researchers get the findings?

A．By analyzing causes.

B．By providing examples.

C．By making a list of facts.

D．By making comparison.

3. What does the research show according to the last paragraph?

A．The proper contact time with dogs still needs further study.

B．Dogs have more effects on the children in special schools.

C．The children doing more exercises have the lowest stress level.

D．The children spending most time with dogs are lowest in stress.

4. What can be the best title for the text?

A．Students need the company of dogs

B．Classroom dog dates reduce kids’ stress

C．A new research about dogs is carried out

D．Dog assisted activities become popular in UK

【推荐1】You're out to dinner. The food is delicious and the service is fine. You decide to leave a big fat tip. Why? The answer may not be as simple as you think.

Tipping, psychologists have found, is not just about service. Instead, studies have shown that tipping can be affected by psychological reactions to a series of different factors from the waiter's choice of words, to how they carry themselves while taking orders, to the billl's total.

Even how much waiters remind customers of themselves can determine how much change they pocket by the end of the night.

“Studies before have shown that mimicry （模仿）brings into positive feelings for the mimicker, "wrote Rick van Baaren, a social psychology professor. "These studies show that people who are being mimicked become more generous toward the person who mimicks.

So Rick van Baaren divided 59 waiters into two groups. He requested that half serve with a phrase such as, "Coming up!" Those in the other half were instructed to repeat the orders and preferences back to the customers. Rick van Baaren then compared their takehome pay. The results were clear-it pays to mimic your customer. The copycat （模仿者）waiters earned almost double the amount of tips to the other group.

Leonard Green and Joel Myerson, psychologists at Washington University in St Louis, found the generosity of a tipper may be limited by his bill. After research on the 1,000 tips left for waiters, cabdrivers, hair stylists, they found tip percentages in these three areas dropped as customers' bills went up. In fact, tip percentages appear to plateau （稳定期）when bills topped $100 and a bill for $200 made the worker gain no bigger percentage tip than a bill for $100.

"That's also a point of tipping," Green says. "You have to give a little extra to the cabdriver for being there to pick you up and something to the waiter for being there to serve you. If they weren't there, you'd never get any service. So part of the idea of a tip is for just being there."

1. Besides service, how many other fectors（因素）affecting the customers' tipping are mentioned in the passage?

A．1	B．2
C．3	D．4

2. These studies show that              .

A．tipping can be affected by physical reactions to many different waiters

B．the mimic waiters can get almost twice as much money as those who don't mimick others

C．people who are being mimicked usually tip less to the person who mimics them

D．mimicry makes the mimicker feel bad

3. According to the passage, which of the following will be likely to show the right change of the tip percentages?

A．	B．
C．	D．

4. We know from the passage that the writer seems to            .

A．object to Mr Green's idea about tipping

B．think part of Mr Green's explanation is reasonable

C．support the opinions of Mr Green and Rick van Baaren about tipping

D．give his generous tip to waiters very often

【推荐3】You are what you eat. This saying has proved scientists with clues about the diet of hominids — our early relatives of 3 million years ago.

Studying carbon atoms locked up in tooth-enamel, two researchers argued against the widely held belief that hominids ate little more than fruits and leaves. Sponheimer and Julia Lee-Thorp of the University of Cape Town, South Africa, report their findings in Friday’s Science.

There aren’t many clues for us to know the life of early hominids. The shape of hominids’ teeth offered the first clues. Large and flat-edged with thick enamel, they looked perfect for eating nuts and fruits, different from the sharp teeth one would want to tear into meat with. The first stone tools, which help in eating meat, didn’t appear until about half a million years later.

Scientists have also found marks on hominids’ teeth with patterns very similar to those in the teeth of modern-day fruit-eaters. Sponheimer and Lee-Thorp tried a new method. They studied the enamel for the carbon-13. Animals that eat grasses have higher carbon-13 levels than those eating fruits and other plants.

What they found was that the teeth of the hominids had an in-between amount of carbon-13, which meant not only they were eating fruits, they were eating a lot of grasses, or animals eating grasses. The lower carbon-13 levels could also come from eating certain types of insects,

But there are people who understand differently. Prof. Ungar of the University of Arkansas agrees the study offers new suggestions of hominid-diet, but disagrees about the suggestion that meat could explain the lower carbon-13 levels.

One suggestion might be true, though take good care of your teeth. In 3 million years, scientist might be using them to figure out what you ate for dinner.

1. The underlined word “hominids” means ________.

A．prehistoric animals living only on fruits and leaves

B．creatures that lived in the past, which humans developed from

C．ancient human-like animal never eating fruits and leaves

D．a certain type of insects with an in-between level of carbon-13

2. The two scientist’s finding were mainly based on the study about________.

A．the shape of hominids’ teeth	B．the teeth marks of early fruit eaters
C．the grasses of 3 million years ago	D．the make-up of the teeth enamel

3. What is it that Prof. Ungar finds doubtful?

A．Hominids possibly ate grass-eating animals.

B．Hominids probably took good care of their teeth.

C．Hominids were basically fruit and grass-eaters.

D．Meat may explain the lower level of carbon -13.

4. The writer put forward the last suggestion to ________.

A．lead in more eco-topics	B．arouse people’s awareness of dental health
C．to bring some fun to the readers	D．emphasize the importance of what you eat

【推荐1】Singles Day falls on every November 11th, and as the name suggests, this relatively new holiday is one only for people who are still living single lives. I was a bit surprised when I googled ‘Singles Day’ on the Internet, to find that China is the only country in the world that has set aside a special day for singles to celebrate their lives.

*The Origin of Singles Day

An old story goes that once there were four single men, leading very boring lives. None of them were married, or had lovers, or did anything exciting. They just sat around all day and played Mahjong.

One day they played Mahjong from 11 in the morning until 11 at night. During the game, no matter who won, the winning card was always the ‘four columns’ card (the card shows four independent, parallel (并行) columns in two lines). Even more of a coincidence (巧合), it was Nov 11, or 11/11. In order to remember the day, they called it Singles Day.

*University culture

Singles Day was first celebrated at various universities in Nanjing, capital city of Jiangsu Province during the 1990s. It got the name Singles Day because the date consists of four “ones”. These college students have since graduated, and carried their university tradition into society, Singles Day is now a special day for all fashionable youths.

*______

The main way to celebrate Singles Day is to have dinner with your single friends, but it’s important that each person go Dutch to show their independence. People also hold “blind date” parties trying to say goodbye to their single lives.

For breakfast on Singles Day, singles often eat four youtiao representing the four “one” in “11. 11” and one baozi representing the middle dot.

Many singles also choose to say goodbye to their single lives on this day. Many attend “blind date” parties and many people choose to marry on this day. In addition to meaning “single”, the four “ones” of the date can also mean “only one” as in “the only one for me”, some people will use this date and this meaning to tell their special someone that they are the only “one” in their heart.

1. Singles Day got its name because ______.

A．single persons celebrate the day	B．the date is made up of four “one”
C．it was first celebrated at universities in Nanjing	D．the persons who play mahjong are four single men

2. Singles Day ______.

A．is celebrated not only in universities but also in society	B．is celebrated mainly by holding “blind date” parties
C．was first celebrated in the early 21st century	D．was first celebrated by playing Mahjong

3. Which of the following fits in the blank best in the passage? ______

A．Special breakfast.

B．The only one for me.

C．Creative celebration.

D．Saying goodbye to single lives.

4. It can be inferred from the passage that ______.

A．each of the singles doesn’t pay for their own meal while having dinner together

B．many singles often eat four youtiao and one baozi for breakfast every morning

C．many singles attend parties where blind people are present on Singles Day

D．Singles Day is very popular with young people in particular in China

【推荐2】Humankind has tried to improve its standard of living since the very beginning of civilization. Back then, as well as today, providing food and security was the basic task for a person. However, nowadays the range of required goods has expanded significantly. People feel the need for not only some primary things, such as a piece of bread and a roof over their heads, but also for various facilities and luxuries. Providing humanity with these things is connected to the use of natural resources, which requires energy. In turn, the common sources of energy we use today cause pollution, so economic growth is almost inevitably associated with environmental damage.

Economic growth is the increase in numbers of goods and services produced over time by an economy, and it's calculated in terms of real Gross Domestic Product (GDP). Before growth is calculated, inflation(通货膨胀) is adjusted in order to take into account its misleading effect on the price of goods and services. Economic growth can also be explained as the increase in expected output, which results from an increase in actual output, or total demand.

There are certain aspects of economic growth which affect the environment. The first of these is the fact that in order to produce more goods and products, at a faster rate, the construction of large industrial plants is required. These plants produce a lot of waste, leading to the pollution of water and the atmosphere, which may cause negative long- term health effects to nearby populations of animals, or people. They also lead to global warming.

Industrial manufacturing leads to the constantly increasing energy consumption. The traditional energy sources, which are commonly used nowadays, are considered to be the greatest polluters to the environment. There also exist so-called eco-friendly sources of energy. They are sometimes preferred but replacing the traditional sources with them also requires time, during which people have to make some sacrifices to support these undertakings.

In order to produce economically practical energy, a sometimes significant transformation of the natural site is often inevitable. This is expensive and, has harmful effects on the environment. Application of wind energy would Block airflows' natural speed, which is the reason for their decrease in strength, after crossing the windmill. Consequently, the pressure balance that is brought about by this current will be affected, and it is important to remember that the environment and weather conditions are directly affected by atmospheric pressure.

For these reasons, bringing about economic growth without resulting in any environmental damage is impossible.

1. What does the passage mainly talk about?

A．Pollution caused by plant construction

B．Effects of windmills on the environment

C．Economic growth and human civilization

D．Economic growth and environmental damage

2. According to the passage, the author holds the opinion that ____.

A．economic growth should be calculated in terms of GDP

B．use of natural resources causes no damage to the environment

C．industrial manufacturing may cause damage to the environment

D．a windmill is a perfect way to produce economically practical energy

3. Which of the following shows the structure of the passage?
CP (Central Point)        P (Point)          Sp (Sub-point次要点)       C (Conclusion)

A．

B．

C．

D．