Using technology, of course. While special services via webcam(摄像头) and cheating detecting software have been developed now, Mettl, an online company, has developed advanced techniques for netting cheaters, which the company claims are even more reliable and easier to use. Whatever small attempt to cheat, he or she will be found out.

    Mettl has adopted a handful of technologies on its test—taking platform, creating a mini monitoring state in an exam. Here's how it works: A test-takersigns on to Mettl and selects hisher exam from the site's library of pre—loaded tests. Facial and keystroke recognition technology confirm the person that has signed in is the very person, and the system records both the test—taker(through the webcam)and the test—taker's screen throughout the test.

    Mettl's technology uses the test—taker's webcam to detect how many people are using the computer. Soon, it will track eye movement well enough to sense whether the test-taker is looking away from the screen, perhaps to Consult a smart phone or a friend in secret. Mettl also monitors the test-taker's screen and can detect when the test-taker has changed a computer or moved from the test. The system will soon be able to record sound, thus detecting whether the test-taker is talking or being talked to.

    If any irregularities are detected, the system flags the incident and reports it back to the test's administrator. This can bring any number of things, depending on the test-giver's wishes: a completeshutdown of the exam, a warning message that appears on the test-taker's screen, even human instructions from the control center.

    Mettl is hoping its technology will help it break into the country's big MOOC markets.

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

    Green is an important color in nature. It is the color of grass and the leaves on trees. It is also the color of most growing plants.

    Sometimes, the word “green” means young, fresh and growing. For example, a greenhorn is someone who has no experience. In the 15th century, a greenhorn was a young cow or an ox whose horns(角)had not yet developed. A century later, a greenhorn was a soldier who had no experience in war. By the 18th century, a greenhorn had the meaning it has today—a person who is new in a job.

    Someone who is good at growing plants is said to have a green thumb(大拇指). The expression comes from the early 20th century. A person with a green thumb can make plants grow quickly and well.

    Green is also the color used to describe the powerful feeling , jealousy(嫉妒). The green-eyed monster （怪物）is not a dangerous animal from outer space. It is an expression used about 400 years ago by the British writer William Shakespeare in his play “Othello”. It describes the unpleasant feeling when someone has something he wants. For example, a young man may suffer from the green-eyed monster if you get a pay rise and he does not.

    In most places in the world, a green light means to move ahead. In everyday speech, a green light means agree to continue with a project.

    Apps such as Snapchat already give users the ability to add dog ears, colorful hats and other images onto smart phone photos. Virtual(虚拟的)mirrors are a little different. They are designed to let users see what they would look like wearing something that they might want to buy, such as eyeglasses and earrings.

    A smart mirror is an app that turns the screen of a smart phone or other mobile device (装置) into a mirror, using its camera. As users look at the image(影像), the app will make it appear as if they are wearing the object. These smart mirror Apps are becoming popular among retail(零售的))businesses, which want to get people into their stores.

    Peter Johnson is with FaceCake Marketing Technologies. He said, “Virtual try-on off the ability to try on a great many objects, many more than they would be able to try on if were no such kind of App.” Recently, Johnson showed how an app called Dangle works. It lets store customers try on different earrings(耳环)without touching a single pair Dangle can be used on a computer. It uses the app's facial recognition technology to make it appear as if the user is wearing earrings. The earrings in the image appear almost real.

With Dangle, retailers can show customers all of their earrings in a short period of time—something almost impossible without technology. There are other good reasons to use the app. Trying-on goods with the virtual mirror means there is nothing to damage, lose or at risk of being stolen.

    Alec Gefrides is with the American technology company Intel. “We always hear about the big store closings,” said Gefrides. “But Intel sees technology becoming more important in providing customers with a better experience.”

    Crown shyness(树冠羞避) is a mysterious natural phenomenon in which the crowns of some tree species do not touch each other, but get separated by a gap clearly visible from ground level. The effect usually occurs between trees of the same species, but has also been observed between trees of different species.

    There are many theories going around, most of which make sense, but no one has been able to prove without the shadow of a doubt why some trees avoid touching each other.

    In his 1955 book Growth Habits of the Eucalypts, Australian forester M.R. Jacobs writes that the growing tips of the trees are sensitive to abrasion(擦伤), which results in crown shyness phenomenon. This theory was also supported by Dr. Miguel Franco. Some experiments have shown that if trees displaying crown shyness are artificially prevented from swinging in the wind and touching each other, they gradually fill up the gaps between them.

    But while the above theory is arguably the most widespread, it's certainly not the only one. Some scientists have suggested that crown shyness is a mechanism to stop the spreading of leaf-eating insects. These pests have been known to work together and create structures that extend up to 10 cm off of tree branches in order to reach other plants, so the gaps are the trees' natural defense method.

    One Malaysian scholar studied many trees, but found no traces of abrasions, despite their clear crown shyness. Instead, he suggests that the growing tips of the trees were sensitive to light levels and stopped growing when they got too close to other trees. Plants are able to sense how close they are to other plants and in order to get more light, they give off some chemical element to stop other trees from growing too close.

    Whatever the reason, one thing is for sure: plants are more intelligent than people used to think.

    While famous foreign architects are invited to lead the designs of landmark buildings in China such as the new CCTV tower and the National Center for the Performing Arts, many excellent Chinese architects are making great efforts to take the center stage.

    Their efforts have been proven fruitful. Wang Shu, a 49-year-old Chinese architect, won the 2012 Pritzker Architecture Prize—which is often referred to as the Nobel Prize in architecture—on February 28. He is the first Chinese citizen to win this award.

    Wang serves as head of the Architecture Department at the China Academy of Art (CAA). His office is located at the Xiangshan campus (校园) of the university in Hangzhou, Zhejiang Province. Many buildings on the campus are his original creations.

    The style of the campus is quite different from that of most Chinese universities. Many visitors were amazed by the complex architectural space and abundant building types. The curves (曲线) of the buildings perfectly match the rise and fall of hills, forming a unique view.

    Wang collected more than 7 million abandoned bricks of different ages. He asked the workers to use traditional techniques to make the bricks into walls, roofs and corridors. This creation attracted a lot of attention thanks to its mixture of modern and traditional Chinese elements (元素).

    Wang's works show a deep understanding of modern architecture and a good knowledge of traditions. Through such a balance, he had created a new type of Chinese architecture, said Tadao Ando, the winner of the 1995 Pritzker Prize.

    Wang believes traditions should not be sealed in glass boxes at museums. "That is only evidence that traditions once existed," he said.

    "Many Chinese people have a misunderstanding of traditions. They think tradition means old things from the past. In fact, tradition also refers to the things that have been developing and that are still being created," he said.

    "Today, many Chinese people are learning Western styles and theories rather than focusing on Chinese traditions. Many people tend to talk about traditions without knowing what they really are," said Wang.

    The study of traditions should be combined with practice. Otherwise, the recreation of traditions would be artificial and empty, he said.

    On Sunday, November 3, 2019, most North Americans will mark the end of Daylight Saving Time (DST) by moving their clocks back an hour. This simple action will not only add an extra 60 minutes to their weekend, but also shift (变换，变动) daylight back into the morning hours, making it a little less painful to wake up for school and work during the shorter winter days.

    Operating the clocks was first suggested by Benjamin Franklin in 1784. He mentioned the idea in a letter to the editor of the Journal of Paris and advised it should be a way to save candles, but it was not taken seriously. George Hudson from New Zealand also recommended moving the clocks back two hours in 1895 to get extra daylight time to study insects. Unfortunately, neither he nor British people William Willett, who suggested it in 1907 as a way to save electricity costs, got their wish.

    It was the German Empire that began the clock shifting tradition on April 30, 1916, to save fuel needed to produce weapons and bombs for World War I. Though a few others, including the US and Britain, adopted the tradition shortly after, all the countries returned to Standard Time once the war ended, only to start DST again during World War II. Once the battle ended in 1945, the US government ended DST nationally but allowed states and districts to continue the tradition and even allowed them to establish their own start and stop dates.

    However, though there have been many attempts to persuade lawmakers to end DST, both in the US and Europe, they have not been successful. Therefore, unless you live in places like Hawaii and Arizona, you have little choice but to "Fall Back" and enjoy the extra hour this weekend! Health experts suggest the best way to adjust is going to bed at your regular time, even if the day is an hour longer.