1 . We usually think of archaeology as lots of painstaking work by brave explorers. But today, long-hidden cities are being revealed (显露) from the air, where modern archaeologists use laser pulses (激光脉冲) to discover the sign of ancient life buried below thick surface.   

Lidar, short for “light detection and ranging”, needs directing rapid laser pulses at the ground from an airplane. Software catches the time and wavelength of the pulses reflected from the surface and connects it with GPS and other data to produce a precise 3D map of the landscape below.

In recent years, lidar exposed an ancient city in western Mexico called Angamuco. The discovery of this long-lost Mexican metropolis (大都) is especially meaningful.

“To think that this large city existed in the heartland of Mexico for all this time and nobody knew it was there is kind of amazing,” says Chris Fisher, an archaeologist at Colorado State University who led the expedition.

The city extended over ten square miles. “That is a huge area with a lot of people,” says Fisher. “You are talking about 40. 000 building foundations, which is about the same number of building foundations that are on the island of Manhattan.” Archaeologists were surprised when they saw Angamuco’s city plan. The monuments (纪念碑) were largely concentrated in eight zones around the edges rather than being located in one large center.

Archacologists discovered signs of the buried city in 2007 and attempted to explore it using a traditional way. But the team soon realized that it would take at least ten years to outline the whole metropolis. In 2011, they began using lidar to map nearly 14 square miles. Researchers now believe that more than 100. 000 people lived in Angamuco from about AD 1000 to AD 1350. That makes it the biggest city in western Mexico at the time or at least the biggest city we know about so far.

“Everywhere you point the lidar instrument, you find something new.” says Fisher. “Right now. every textbook has to be rewritten. and two years from now. they’re going to have to be rewritten again.”

The term Xuan paper first appeared in On Famous Paintings through the Ages, a book     1     (write) by Tang Dynasty (618-907) scholar Zhang Yanyuan, in which he     2     (describe) Xuan paper as an ideal carrier for calligraphy and painting. Handmade Xuan paper from Jingxian county, East China’s Anhui province, was listed     3     a tribute for its super quality during the period.

The traditional craft of making Xuan paper is     4     (high) demanding, Sandalwood bark (檀香树皮),     5     plant native to southern China, goes through 108 procedures over the course of three years before it can transform into fine Xuan paper. Because of the entire procedure     6     is so complex, even the most skilled craftsman can only master limited number of steps.

The flow of ink, both guided and resisted by water, determines the output of Chinese art, and Xuan paper outshines others with its excellent ability     7     (make) the best use of ink. Different Xuan paper can     8     (create) for artistic expression in freehand ink paintings or calligraphy.

Unlike other forms of paper, Xuan paper is very resistant to damage brought by time.     9     (it) durability (耐久性) has made the preservation of many valuable     10     (work) from ancient China possible.

Before the Tangshan Earthquake, Strange things    1    (happen) in the countryside. For several days, the water in the village wells     2       ( rise) and fell. There were deep cracks     3       appeared in the well walls. At least one well had some     4     (smell) gas coming out of it. Chickens and even pigs were too nervous     5     (eat), and dogs refused to go inside buildings.    6     (mouse)ran out of the fields looking for places to hide, and fish jumped out of the water. At about 3:00 a.m.,    7    28 July 1976, bright lights     8     (see) in the sky outside the city of Tangshan and loud noises were heard.       9       the city’s one million people were asleep as usual that night.     10       (fortunately), it led to a lot of people losing their lives.

With a history of more than 2,000 years, the Silk Route dates back to Han dynasty. Through this route, the Chinese highly qualified silk made     1    (it) fame to the Western countries. The merchants in different regions     2    (seek) the opportunity of trading Chinese silk and they indeed made their fortune along this route. That route functioned     3     the life blood of international trade at that time. Meanwhile, the Chinese civilization     4    (introduce) to the Western countries and vice versa. The Silk Route was considered as a new chapter     5    (record) the friendship between the European and Asian peoples.

Throughout all these years, many great figures have made significant     6    (contribute) to the development of the Silk Route. Today, the Silk Route has a poetic name called One Belt One Road, aiming to help those     7    (connect) regions in culture and economy exchange with     8     more advanced road. The main cities alongside it are becoming     9    (large) and more important in helping trade and culture exchange. Many countries have gained great benefits along the trading process. All in all, the ancient Silk Road is more like a historical textbook for everyone to read and to know about     10     happened during that ancient time. It has been playing a significant role in the development of the civilizations of China.

6 . On Wednesday, a search team called Endurance 22 announced that it had located the wreck (沉船) Endurance. The Endurance was found 1. 87 miles below the ocean’s surface, about four miles south of its last known location near Antarctica. The ship sank after it got trapped in the ice in the Weddell Sea in 1915.

The discovered ship is still in excellent shape. The name can be clearly read on the back of the ship. Its wheel looks ready to be turned. Even though the ship is made of wood and is over 100 years old, it has survived with little damage. Scientists say that the small organisms (微生物) that normally break down wooden objects underwater don’t live in cold water around Antarctica.

The Endurance 22 is led by the Falklands Maritime Heritage Trust. The team ran the project from an ice-breaking ship which was able to handle the difficult conditions of the Weddell Sea. To locate the Endurance, the team used two underwater robots called Sabertooths, which were especially useful, since they could travel under the ice and go where the ship could not. The robots were looking for anything sticking up above the seafloor. For the last two weeks, the Sabertooths robots have been scanning the seafloor in a 150-square mile area around the Endurance’s last known location. Last Saturday, the ship was found. After the ship was located, the Sabertooths used high-quality cameras and scanners to record the Endurance in detail.

The Endurance is expected to remain untouched. Antarctica’s waters are protected by an international agreement, which means the ship can’t be disturbed. The Endurance 22 team plans to create a digital 3D model of the wreck site, using a careful scan they made. This will allow scientists to study the ship in detail without disturbing it.

As we all know, China has countless     1    (attract). The Great Wall is probably one that is most familiar     2     the Western tourists. The Great Wall is like a giant stone dragon,     3    (wind) across the country from the ocean on the east-to the desert on the west. It     4    (be) the longest wall that has been built ever, 1, 500 miles in    5    (long). Along the wall are watch towers,     6     soldiers were on the watch for threats. The wall was     7    (origin) constructed to prevent invasion of neighboring states, and the majority of the existing wall is from the Ming Dynasty. From the top of the Great Wall, people can enjoy     8     impressive view of continuous mountains, green trees and blooming wild flowers. If we were to build such a wall now, we would use modern machines.     9    , the ancient Chinese had to build the wall by hand. The reason why the Great Wall attracts tourists from all over the world every year is that it     10    (represent) the highest wisdom of ancient China. Just as the saying goes, “He who has never been to the Great Wall is not a true man.”