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单选题4. They're going to build a big office block on that ______ piece of land.

单选题Questions 1 to 10 are based on the following passage.Although interior design has existed since the beginning of architecture, its development into a____1____field is really quite recent.Interior desi

单选题. Questions 1 to 4 are based on the conversation you have just heard.1.

单选题Questions 1 to 5 are based on the following passage.Latino youths need better education for Arizona to take full advantage of the possibilities their exploding population offers.Arizonas fast-gro

单选题Questions 1 to 5 are based on the following passage.For expat parents, passing on their native languages can be a struggle.Not sharing your first language with loved ones is hard.Not passing it on to

单选题Sugar—Friend VS EnemyASugar is everywhere.Its in our drinks, its in our foods, and its hidden in places we never would think of.Many would call sugar their friend in time of need, but i

单选题. Questions 19 to 22 are based on the recording you have just heard.4.

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单选题 Being somewhat short-sighted

单选题32. China has greatly ______ its influence in world affairs.

单选题Questions 1 to 10 are based on the following passage.The ocean covers 70.8% of the Earths surface.That share is____1____ up.Averaged across the globe, sea levels are 20cm higher today than they w

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单选题. Is that Folgers coffee in your cup or Maxwell House? Now you no longer have to rely on your nose to tell. Researchers have developed an analyzer that can distinguish between 10 commercial brands of coffee and can even tell apart coffee beans roasted at various temperatures for different times. The advance could help growers determine within minutes whether a particular batch of coffee is just as good as the previous one or whether it's undrinkable. Researchers have been trying for years to come up with a simple way to analyze coffee. But it's no easy task. The challenge is that the pleasant smell of roasted coffee beans consists of more than 1,000 compounds that change with roasting temperatures and time. Traditional methods of chemical analysis generally have difficulty distinguishing between compounds that are very similar to one another. And "electronic noses," an array of dyes, and other devices that change color or chemical properties when they react with certain molecules suffer from the same drawback. Over the past decade, chemist Kenneth Suslick and colleagues at the University of Illinois, Urbana-Champaign, have refined the electronic nose approach. In the new study, they used dyes that interact strongly with other chemicals, malting them more specific. They then put drops of 36 dyes on a polymer (聚合物) film the size of a nickel. The colors in the dyes belonged to a range of chemical classes, including pH indicators and molecules that change color with certain chemical vapors. The device produced a pattern of colors as each coffee's mixture of volatile (易蒸发的) compounds interacted with the dyes. When the investigators pumped vapors from various coffees including Starbucks, Sumatra Roast and Folgers Grande Supreme Decaf-over the arrays, all generated unique color patterns, like a molecular "fingerprint," they report this month in Analytical Chemistry. The array doesn't give any information about the individual compounds in the smell. "The important thing is that we can easily tell the difference between different roastings and coffees," notes Suslick. And that should help growers quickly and cheaply analyze problems with coffee, such as burnt flavors, during their initial screening process, says food scientist Felix Escher at the Swiss Federal Institute of Technology Zurich. The applications for the kind of device created by Suslick's team go beyond coffee, says chemist Pavel Anzenbacher at Bowling Green State University in Ohio. Similar arrays, he notes, could be used in everything from detecting explosives to spotting contaminants (污染物) in water.1. The coffee analyzer developed by researchers is most probably intended for ______.

单选题6. My father seemed to be in no ______ to look at my school report.

单选题. Officials at the White House announced a new space policy focused on managing the increasing number of satellites that companies and governments arc launching into space. Space Policy Directive-3 lays out general guidelines for the United States to mitigate (缓解) the effects of space debris and track and manage traffic in space. This policy sets the stage for the Department of Commerce to take over the management of traffic in space. The department will make sure that newly launched satellites don't use radio frequencies that would interfere with existing satellites, and schedule when such new satellites can be launched. This only applies to American space activities, but the hope is that it will help standardize a set of norms in the dawning commercial spaceflight industry throughout the world. Space, especially the space directly around our planet, is getting more crowded as more governments and companies launch satellites. One impetus for the policy is that companies are already starting to build massive constellations (星座), comprising hundreds or thousands of satellites with many moving parts among them. With so much stuff in space, and a limited area around our planet, the government wants to reduce the chances of a collision. Two or more satellites slamming into each other could create many more out-of-control bits that would pose even more hazards to the growing collection of satellites in space. And it's not like this hasn't happened before. In 2009 an old Russian craft slammed into a communications satellite, creating a cloud of hundreds of pieces of debris and putting other hardware at risk. Journalist Sarah Scoles reports that NASA currently tracks about 24,000 objects in space, and in 2016 the Air Force had to issue 3,995,874 warnings to satellite owners alerting them to a potential nearby threat from another satellite or bit of debris. That's why this new policy also includes directions to update the current U.S. Government Orbital Debris Mitigation Standard Practices, which already require any entity that launches a satellite or spacecraft to vigorously analyze the likelihood that any of their actions, from an unexpected failure or normal operations, will create more space debris. It includes accounting for any piece of debris they plan to release over 5mm that might stay in orbit for 25 years or more. It might seem surprising to think about an item staying in space for that long, but the oldest satellite still in orbit—Vanguard 1—turned 60 in 2018. Agencies and companies throughout the world are working on developing technology that would dispose of or capture space debris before it causes serious damage. But for now, the U.S. government is more focused on preventing new debris from forming than taking the trash out of orbit.1. What is the purpose of the new U.S. space policy?______

单选题. Questions 12 to 15 are based on the passage you have just heard.4.

单选题 When people become unemployed