1 . 听下面一段独白,回答以下小题。
1. What makes Jessica Damiano kill houseplants?A.Carelessness. | B.Forgetfulness. | C.Laziness. |
A.It needs enough sunlight. |
B.It is unsuitable for beginners. |
C.It likes being far from a window. |
A.Characters of houseplants. |
B.Ways to save water at home. |
C.Advice on growing houseplants. |
2 . 听下面一段较长对话,回答以下小题。
1. Why did Tracy bring dogs to the children?A.To teach them to love animals. |
B.To help them gain confidence. |
C.To protect them from dangers. |
A.They may misbehave. |
B.They may get hurt. |
C.They may carry diseases. |
A.Give a talk. | B.Meet the children. | C.Take some photos. |
3 . The green and red watermelon is a sweet, refreshing summer snack. But it wasn’t always so sugary or brightly colored. So what did watermelons originally taste and look like, and from where did they come?
The fruit isn’t from the Fertile Crescent of ancient Mesopotamia, as so many other domesticated (家养的) crops are, research shows. Susanne Renner, a scientist, and her colleagues carried out comprehensive genetic sequencing (基因测序) of the domesticated watermelons — the kind you might find on supermarket shelves — along with six wild watermelon species.
“We found the modern genomes (基因组) of the domesticated watermelon are more closely related to the Sudanese wild type than any other that we analyzed,” she said. The Sudanese wild watermelon has some obvious differences from the domesticated version. “The flesh is white and not very sweet, and it’s mainly used as animal feed,” Renner said. Nevertheless, the genetic similarity between the two species led the researchers to conclude that the Sudanese fruit is probably a precursor (前身) to the red and sweet domesticated watermelon.
It’s likely that ancient farmers grew non-bitter varieties of the wild watermelon and thus increased its sweetness over many generations through the domestication process. The red color is probably also thanks to artificial selection, in which farmers likely favored and selectively bred red fruit.
We already knew that the ancient Egyptian king Tutankhamun was buried with watermelon seeds 3,300 years ago, yet that isn’t sufficient proof of a domesticated, sweet watermelon. But then, Renner found an image of a watermelon-like fruit on an ancient Egyptian tomb painting, thought to be more than 4,300 years old. In a separate tomb, another image showed the watermelon cut up in a dish alongside other sweet fruits. This realization, coupled with Renner’s genetic findings, suggests that the watermelon was most likely domesticated around that time either in Egypt or within trading distance of the ancient empire.
“Historically speaking, that’s a very significant finding,” said Hanno Schaefer, a professor of plant biodiversity. “It’s becoming clearer that we’ve greatly neglected the North African region. We’ve focused too much on the Fertile Crescent and we need to invest more resources into studying the agriculture of North Africa.”
1. What can we learn about the Sudanese wild watermelon?A.It is brightly colored and sugary. |
B.It is consumed mainly by animals. |
C.It has no connection with the domesticated type. |
D.It has more differences than similarities to the domesticated type. |
A.More resources will be devoted to agriculture research in South Africa. |
B.The domesticated watermelon has a history of at least four thousand years. |
C.The domesticated watermelon probably developed from the Sudanese type. |
D.Few domesticated crops are from the Fertile Crescent of ancient Mesopotamia. |
A.The history of the Sudanese wild watermelon. |
B.Where wild watermelons actually come from. |
C.The characteristics of domesticated watermelons. |
D.How domesticated watermelons came into being. |
A.Favorable. | B.Doubtful. | C.Critical. | D.Tolerant. |
4 . Tropical cyclones(热带气旋), including hurricanes and typhoons, are now moving at a slower speed than they did decades ago, new research shows.
While having a cyclone travel with less speed may seem like a good thing, it’s actually just the opposite. Wind speeds within the storm remain high, but the whole system itself moves slower, allowing punishing rains to stay longer over communities. “Nothing good comes out of a slowing storm,” says James Kossin, author of the paper. “It can increase the amount of time that buildings suffered from strong wind. And it increases rainfall.”
In his paper, Kossin showed that from 1949 to 2016, tropical cyclones across the globe slowed their movement by 10 percent on average. In some regions (地区), the speed of those storms slowed even more as they hit land. In the western North Pacific, the decrease was much more manifest—almost a third. That means a storm that may already hold more moisture (水分)will have time to drop more of it in each spot.
Kossin’s work was based on details of almost 70 years’ worth of storms, but he didn’t try to determine what was causing the slowdown. Still, the change is exactly what he and other cyclone experts said, which would be expected from climate change. With the polar regions warming faster than other parts of the globe, that is changing the pressure and reducing the winds that push these storms.
Christina Patricola, a scientist, called Kossin’s work important and new and said she found it reliable. “I was not surprised by his findings,” she says. “But I was surprised by the speed of the slowdown.”
Kossin hopes that scientists will begin building models that show which places are likely to face the most risk. Given that storms in some regions are moving towards polar regions and already increasing in intensity(强度), cyclones causing unusually powerful rain may threaten places not normally in their paths. Scientists must take action to make those places suffer less from the disasters.
1. Why is the decrease in cyclones’ speed a bad thing?A.It leads the cyclones to move faster on the ground. |
B.It causes the cyclones to have higher wind speed outside. |
C.It makes hard rains and strong wind last longer in one place. |
D.It results in more typhoons taking place in some communities. |
A.Obvious. | B.Satisfying. | C.Confusing. | D.Impossible. |
A.Climate change in the polar regions is under control. |
B.Scientists find it hard to understand the slower cyclones. |
C.Scientists should do further experiments in polar regions. |
D.Climate change may be the cause of the slowdown of the cyclones. |
A.To find out the normal paths of serious cyclones. |
B.To prove the speed of the cyclones can be controlled. |
C.To reduce the damage from cyclones to possible areas. |
D.To call on scientists to focus on the danger of climate change. |
5 . My family always had some sort of animal around, but none of them were truly mine. My parents didn’t permit me to
Every Friday I would clean out his bowl. I found myself
One day, I came home from school and headed to my room to
My mom walked into my room. I turned around as tears started to well in my eyes. “Mommy, George d…d…died.” With that
Suddenly, I realized that George hadn’t just
A.draw | B.imagine | C.have | D.share |
A.doubtful | B.excited | C.surprised | D.afraid |
A.toy | B.mind | C.time | D.pet |
A.take care of | B.make use of | C.get hold of | D.look forward to |
A.reading out | B.putting away | C.turning down | D.showing off |
A.replaced | B.recognized | C.affected | D.needed |
A.feed | B.save | C.impress | D.find |
A.basic | B.terrible | C.funny | D.familiar |
A.dropped | B.emptied | C.hid | D.checked |
A.common | B.last | C.extra | D.new |
A.left | B.reminded | C.defeated | D.chosen |
A.preference | B.independence | C.difficulty | D.responsibility |
A.safe | B.good | C.sorry | D.tired |
A.agreement | B.treatment | C.disappointment | D.achievement |
A.Otherwise | B.Besides | C.However | D.Therefore |
6 . 听下面一段独白,回答以下小题。
1. How many communities is the district made up of?A.23. | B.24. | C.25. |
A.20℃. | B.30℃. | C.40℃. |
A.Spring. | B.Summer. | C.Autumn. |
A.Skating. | B.Boating. | C.Both A and B. |
7 . The fruit-tree pinhole borer (针孔蛀虫), as its name implies, makes holes in fruit trees. It lays its eggs and raises its young in the galleries thus created . Yet the beetles (甲虫) do not feed directly on the wood they bore into. Instead, they devour fungi (真菌) that grow on the wood thus exposed.
Researchers have long suspected that this is a form of farming, because they have evidence that the beetles carry spores (孢子) of their preferred crop, R. sulphurea, into their smallholdings—in effect, sowing it there.
Observations of natural fruit-tree pinhole-bore r dwellings suggest that R. sulphurea grows in them more abundantly (大量地) than might be expected, given all the fungal competition around—but not why. To check whether the beetles are, indeed, weeding their crop, Janina Diehl and Peter Biedermann of the University of Freiburg did an experiment.
In the laboratory, they had mother beetles of the little wood bore restablish nests, in which the typical fungal gardens formed. But before the beetles had started laying their eggs, they collected all of the beetles and then returned half to their dwellings while leaving the other nests empty. Genetic analysis of the fungal gardens after 40 days showed that the presence of the beetles had greatly changed the fungal community. Twenty days after that, they sampled the gallery walls for fungi.
As they had hoped and expected, R. sulphurea was much more abundant in beetle-tended galleries than in those without residents. In the former, it made up half of the fungal mass extracted. In the latter, less than a third. These beetles are indeed weeding their crop.
“Further research into how exactly the beetles suppress the growth of weed fungi could alsoprovide worthwhile insights for human agriculture, which is struggling with weed resistance, for example,” says Biedermann. “It’s highly exciting for us to see how nature has been doing this for 60 million years. We humans can still learn something from these mechanisms.”
1. What does the underlined word “devour” in paragraph 1 mean?A.Sow. | B.Tend. | C.Eat. | D.Move. |
A.The number of the mother beetles. | B.The presence of the beetles. |
C.The quality of food fungi. | D.The types of weed fungi. |
A.They weed crops. | B.They feed on fruit. |
C.They live in groups. | D.They lay eggs in trees. |
A.The research findings are of little value. |
B.Measures should be taken to protect the beetles. |
C.Fungi cause much damage to human agriculture. |
D.Further research to the beetles might benefit farmers. |
8 . Baleen whales (须鲸), such as the blue whale, are huge sea animals. “Baleen” describes a filter-feeding (滤食的) system in their mouths through which they can eat huge numbers of very small ocean animals. But it appears now that whales are not the first sea animals to filter-feed.
Scientists recently reported their findings about the ancient remains of a sea animal called Hupehsuchus nanchangensis that lived 248 million years ago, during the Triassic Period. They say its fossil (化石), which was unearthed in China’s Hubei Province, presents evidence of a filter-feeding system similar to that of baleen whales.
Unlike blue whales, Hupehsuchus was not large. The animal measured about one meter long. Its mouth was narrow and toothless. Its lower jaw was loosely connected to the rest of the head bone. This permitted the animal to open its mouth wide to take in a large amount of water and the animals it carried. The structure traps little sea animals but lets the seawater flow out.
From two new fossils with well-kept head bones the scientists found evidence along the jaws suggesting the presence of soft tissue s that could have served as baleen. “We were amazed to discover the adaptation in such an early sea animal,” said Fang Zichen of the Wuhan Center of China Geological Survey.
Paleontologist Mike Benton said, “Altogether, this points to a soft pocket of skin around the mouth and throat, as in modern baleen whales, and some kind of filtering device hanging from the jaws, like baleen.” But, he added, the baleen and skin were not fossilized.
According to scientists, Hupehsuchus’ feeding style would match that used by baleen whales. This feeding structure is an example of a phenomenon in which distinct organisms independently evolve similar features—like the wings of birds and bats—to adapt to similar environments.
1. Why are baleen whales mentioned in the first paragraph?A.To present another sea animal. | B.To awaken curiosity about huge whales. |
C.To draw attention to their current state. | D.To introduce their unique feeding pattern. |
A.How it filter-fed. | B.Its lower jaw's function. |
C.Why it grew toothless. | D.Its physical characteristics. |
A.Baleen surrounded the jaws. | B.It could feed and live in the sea. |
C.It developed a filter-feeding system. | D.Two undamaged head bones were found. |
A.Hupehsuchus Proving to Be a Filter-feeder |
B.Hupehsuchus Appearing Earlier than Whales |
C.Scientists Unlocking the Secrets of Hupehsuchus |
D.New Evidence Telling Hupehsuchus'Evolution |
1. What did the Police in Brazil’s Bahia state vote to do?
A.To end a strike. |
B.To celebrate the 2014 World Cup. |
C.To prevent the carnival celebrations. |
A.At least 6. | B.At least 8. | C.At least 10. |
A.45. | B.40. | C.35. |
A.On Wednesday. | B.On Friday. | C.On Sunday. |
1. What’s the size of the redwood forest in Muir Woods National Monument?
A.240 acres. | B.319 acres. | C.559 acres. |
A.Less than 400 years old. | B.400 to 800 years old. | C.More than 1 ,000 years old. |
A.Dry and sunny. | B.Wet and rainy. | C.Wet and foggy. |
A.New York. | B.San Francisco. | C.Los Angeles. |