1 . Avi Loeb, a scientist, believes that we are not alone in the universe. The belief fits with Loeb’s alien (外星的) spaceship theory that at least one alien spaceship might be flying over the orbit (轨道) of Jupiter, which won the international attention last year.
Astronomers in Hawaii found the first known interstellar (星际的) object in late 2017. It was a bit of light moving so fast past the sun that it could only have come from another star. Almost every astronomer on the planet was trying to figure out how the object, called “Oumuamua” got to our far-away, part of the Milky way galaxy. “One possibility is that ‘Oumuamua’ is debris (碎片) from an advanced technological equipment,” Loeb said. “Technology comes from another solar system just showed up at our door.”
“‘Oumuamua’ is not an alien spaceship,” Paul Sutter, another scientist wrote. He suggested Loeb was seeking publicity. Most scientists think “Oumuamua” is some sort of rock. They think it could be an icy wandering comet.
Loeb says that “Oumuamua’s” behavior, means it can’t be a block of rock shaped like a long photo. He thinks it's more likely an object that’s very long and thin, perhaps like a long pancake or a ship’s sail. Loeb says that if someone shows him evidence that contradicts his beliefs, he will immediately give in.
Loeb believes himself a truth-teller and risk- taker in an age of very safe, too-quiet scientists. “The worst thing that can happen to me is that I would be relieved of my management duties, and that would give me even more time to focus on science,” Loeb says. He said he wouldn’t mind giving up all the titles he had and returning to the Israeli farming village where he grew up.
1. What does Loeb say about “Oumuamua”?| A．It is an icy comet. |
| B．It looks like a long photo. |
| C．It is actually some sort of rock. |
| D．It may come from another alien civilization. |
| A．Searches for. | B．Depends on. |
| C．Turns to. | D．Goes against. |
| A．He is foolish. |
| B．He is unsatisfied with his titles. |
| C．He is a firm believer in scientific truth. |
| D．He is uncertain about his career future. |
| A．Have Aliens Paid a Visit in Spaceships? |
| B．Do We Really Know about Space Theory? |
| C．Scientists Are Working on High Technology |
| D．Astronomers Are Encouraging Space Travel |
2 . It appears to fit with most people's experience: how Christmas seems to come around quicker every year? Questionnaires by psychologists have shown almost everyone feels time is passing faster now compared to when they were half or a quarter as old. Most strikingly, lots of experiment have shown that, when older people are asked to guess how long the time is, or to ‘reproduce’ the length of periods of time, they guess a shorter amount than younger people.
In 1877, Paul Janet suggested the proportional theory, where a child of 10 feels a year as I 10 of his whole life while a man of 50 as 1/50, so the subjective sense of the 50-year-old man is that: these are insignificant periods of time which gallop.
There are also biological theories. The speeding up of time is linked to how our metabolism (新陈代谢)gradually slows down as we grow olden Children's hearts beat faster than They breathe more quickly. With their blood flowing more quickly, their body clocks “cover” more time within the space of 24 hours than ours do as adults. On the other hand, older people are like clocks that run slower than normal, so that they lag behind, and cover less than 24 hours.
In the 1930s, the psychologist Hudson Hoagland found body temperature causes different perceptions of time. Once, when he looked after his ill wife, he noticed she complained he'd been away for a long time even if only away for a few moments. Therefore, Hoagland tested her perception of time at different temperatures, finding the higher her temperature, the more time seemed to slow down for her, and that raising a person's body temperature can slow down his sense of time passing by up to 20%.
Time doesn't necessarily have to speed up as we get older though. It depends on how live our lives, and how we relate to our experiences.
1. What do the questionnaires and experiments find?| A．Time now is shorter than before. |
| B．Aging makes people think slowly. |
| C．The old feel time flies faster than the young. |
| D．The old value time more than before. |
| A．Fly swiftly. | B．Pause briefly. |
| C．Move slowly. | D．Pass stably. |
| A．A kid with slower metabolism. | B．A child with low body temperature. |
| C．A grown-up feeling freezing. | D．An adult with a high fevel. |
| A．How time flies! | B．To live a full life! |
| C．Why time passes at different speeds? | D．How to save more time? |
3 . Standing on the ruins（废墟）after the fire where his house had been, Peter Ruprecht admitted that he was not sure how or when to rebuild. He was still shocked by what Australia's increasingly changeable climate had already delivered: first a drought, then a destructive bush fire, then a foot of rain from a storm.
"It's unstoppable," said Mr. Ruprecht, a former dairy farmer. "We speak about the warmth of Mother Nature, but nature can also be vicious and wild and unforgiving."
Australia's' hellish（地狱的）fire season has eased（缓和）, but its people are facing more than a single disaster. With floods destroying homes not far from where fires recently spread, they are facing a cycle of what scientists call "compound extremes": one climate disaster strengthening the next.
Warmer temperatures do more than just dry out the land. They also heat up the atmosphere, which means clouds hold more moisture（水汽）for longer periods of time. So droughts get worse, giving way to fires, then to heavy rains that the land is too dry to absorb.
Many Australians in disaster zones complain that their government, after ignoring climate change for years, has not yet to draw up recovery plans that are clear and that take future threats into account.
At the same time, the economic costs of a changing climate are rising quickly. Philip Lowe, the governor of the Reserve Bank of Australia, warned recently that Australia was already paying a price, and that it would only go up.
1. Why Peter Ruprecht is mentioned in the beginning?| A．To arouse readers' pity. | B．To introduce the topic. |
| C．To stress the problem. | D．To call on readers to help. |
| A．grateful | B．advanced | C．responsible | D．forcible |
| A．Government inaction. | B．Warmer temperature. |
| C．The lack of money. | D．No recovery plans. |
| A．guidebook. | B．A travel journal. | C．A news report. | D．A book review. |
4 . Biofuels (生物燃料), gained from plants and animal matter, are a key solution to the environmental problems caused by fuels like coal. “Bioalcohol (生物酒精) is the most common biofuel and is produced by sugars found in materials such as corn. With some engine redesigned, it can be used directly by cars, buses, etc.,” says Professor Daniel Tan, “12 percent of transport fuel could come from biofuels, especially bioalcohol, by 2030.”
But a 2016 study of biofuels said, “Bioalcohol presently is mostly produced with food crops. Altogether, the environmentally-friendly biofuels rely on about 2-3 percent of the global water and land used for agriculture, which could feed a large number of hungry people.”
Energy experts have therefore been trying to deal with the problem. Recent research led by an international team found that the agave (龙舌兰) plant might offer a way out. This plant tends to be the right bioalcohol source to supersede others such as sugarcane (甘蔗) and corn.
Daniel Tan explains that the agave can be grown in unfavorable conditions and is not a major food crop. “It can grow in areas that lack water and rainfall without being watered by farmers, and it does not compete with food crops or put demands on limited water. This kind of useful plant is recently being grown in Australia. It can survive Australia's hot summers,” he says.
The study finds that sugarcane produces just a little more fuel per square meter each year than the agave. However, the agave outperforms sugarcane in a range of areas, including pollution to the earth, and water using. The agave uses 69 percent less water than sugarcane and 46 percent less water than corn for the same amount of fuel produced. As for corn，it produces less fuel per square meter each year than the agave.
However, Daniel Tan states: “The first generation of bioalcohol from the agave recently faces a big competition from oil, whose recent low price makes it far more attractive to customers. Without some policy support from the government, bioalcohol production from the agave faces big challenges.”
1. What can we learn about bioalcohol from the first paragraph?| A．It is popular among customers worldwide. |
| B．It is a kind of biofuel made from artificial matter. |
| C．It helps vehicles' engines stay in good condition. |
| D．It can play a big role in making transport fuel green. |
| A．Take the place of. | B．Take advantage of. |
| C．Get away from. | D．Get along with. |
| A．It improves the local weather. | B．It keeps the water in the ground. |
| C．It produces plenty of food for humans. | D．It puts low demands on growing environment. |
| A．Reduce the price of oil. | B．Make some favorable policies. |
| C．Expand agave bioalcohol's production. | D．Introduce competition into agave bioalcohol market. |
