Throughout history, mankind has been working hard on the space     1     (explore) to learn more about the universe though it was thought     2     (possible) before the mid-20th century. However, so many scientists were     3     (determine) to make the human dream to explore space     4     (realize). With the first satellite launched and orbiting around Earth     5     (success), Yuri became the first astronaut     6     (send) into space in 1961. After that, American astronaut Neil Armstrong succeeded in stepping onto the moon. Although the failure of Challenger was     7     (disappoint), human beings went on with their desire to explore the universe, the International Space Station being the best example.

    8     (follow) Russia and America, China became the third country in the world to send humans into space     9     (independent) in 2003,     10     Yang Liwei successfully orbited Earth. From then on, China has made great progress in space exploration. Shenzhou 6 and 7 were sent into space, the Tiangong 2 docked with Tianzhou 1, and Chang’e 4 landed on the moon.

In 1937, the aggression of the Japanese army brought disaster to China's three great     1    (university): Peking University and Tsinghua University     2     (occupy) by Japanese troops, while Nankai University was completely destroyed by bombing.     3     (save) their educational and intellectual heritage, the three universities joined together in Kunming as National Southwest Associated University, otherwise known     4     Lianda.

Despite the immense hardships and the daunting challenges, it was right in this place, over a period of eight long years,     5     the nation's intellectual heritage was not only guarded but fortified by the passion and belief of the worthy academics of Lianda.

With the country at war, students at Lianda were not going to shirk their duty.     6     (drive) by a sense of commitment, a great many joined the army to resist the Japanese invaders and defend the honour of the nation.

A product of the war, Lianda is now     7     (physical) gone.     8     it has become the crowning glory of China's modern universities, not only because of its prominent professors and talented students, but also because of the school's strong spirit of perseverance and     9     (dedicate).

More than eighty years on, the priceless contribution of Lianda still needs to be reaffirmed. It     10     (become) part of the collective memory of the Chinese nation, with its spirit as the blueprint for all universities in China in the modern era.

Code-named "Operation Overlord", it was the     1     (large) combined sea, air and land operation in history, the aim being     2     (free) north-west Europe from German occupation. After waiting for the perfect     3     (combine) of weather, moon and tides, the date for the start of Operation Overlord     4     (set) for 6 June. Supreme Allied Commander General Eisenhower issued an order to the troops. With these words     5     (ring) in their ears, Allied soldiers prepared for what would become known as D-Day.     6     dawn on 6 June, thousands landed by parachute behind enemy lines in northern France. Meanwhile, thousands more were journeying across the English Channel to Normandy,     7     (protect) by fighter planes in the skies above them. Their objective was clear: to reach the Normandy beaches along about 80 kilometres of French coastline. The fiercest fighting was at Omaha Beach. The enemy were hiding, ready to attack the Allied soldiers even before they reached land. Boats were hit and men drowned,     8     those who did make it to the beach faced heavy machine gunfire. By mid-morning, hundreds lay dead in the water and amongst the tanks on the beach. But, despite the high cost in human life, the D-Day landings were     9     success and were seen     10     (wide) as the beginning of the end of the Second World War.

Six “sacrificial pits” (献祭深坑)，    1    （date）back to 3,200 to 4,000 years, were discovered in Sangxingdui site on March 20th. Over 500 artifacts     2     (unearth) from the site. Among them was a gold mark, found at the No.5 pit, with     3     area of about three square meters,     4     was the smallest pit, according to archaeologists.

Sangxingdui site, first found in 1929, is generally considered as one of the     5     (value) archaeological sites along the Yangtze River. However, the large-scale excavation (挖掘) on the site only began in 1986, when two pits widely     6    (believe) for sacrificial ceremonies were accidentally discovered.

    7     the digging process, archaeologists made full use of modern scientific and technological means     8     (build) an archaeological excavation cabin.

So far, archaeologists have dug out     9     (variety) of cultural items from four of the pits. The rest of the     10     (new) discovered pits are still under excavation.

On January 24, 1848, James Marshall, a mechanic, discovered gold in the Coloma Valley of California. Word of this finding    1    (publish)in Eastern newspapers in the fall of 1848 and was further popularized in remarks    2    (make)by James K. Polk in his farewell address. Soon, passenger-loaded ships sailed    3    the East Coast, around Cape Horn, and northward to California.

Within the first year, more than 80 000 prospectors, the Forty-Niners(淘金者), arrived. San Francisco    4    (grow) to a community of 20 000 in a few months. In 1848, the population of California was about 15000. By 1852, California's population topped 250 000. The ranks of new residents were swollen by sailors    5    jumped ship in San Francisco and headed to the gold fields,    6    (leave)their ships too short on crew to continue. California attracted many reputable people,    7    the first to go were the ones with the least to lose and the    8    (few)responsibilities. The predictable result was a rise in crime, which led to the founding of the Sari Francisco Committee of Vigilance(警戒)in 1851.The    9    (discover) of gold transformed California from an underpopulated,    10    (distance) region into an area ripe for statehood.

On a grey afternoon on 19 November 1863, Abraham Lincoln mounted a platform in a field in Gettysburg, Pennsylvania. He was there in memory of the    1    (die)soldiers. The place was the site of a recent battle     2    thousands of soldiers had died.

At that time, America was    3     (bitter) divided. For two years, its people had been deep in a civil war. The Union side won but    4    a great cost. Over 50,000 soldiers    5     (kill)or wounded, and people lost hope and purpose.

Lincoln understood the feelings of the civilian people. His speech gave them hope, belief and a reason     6     (look) to the future. He gave them    7    new vision of what the United States of America should be     8     (base)on the ideals set down by its Founding Fathers 87 years before. It was what the soldiers had died for. Now it was up to the    9     (live) to remove not only the divisions between North and South, but the boundaries between black and white, and work step by step towards the    10     (equal)of humankind.