Columbus was born in a port city of Italy in 1451. As a teenager, he loved sailing and showed great interest in geography,     1     encouraged him to begin his career as a seaman.

Columbus insisted on searching for a direct sea route to the East Indies     2     sailing across the Atlantic Ocean. After continuous efforts, he received support from the King and Queen of Spain. On 3 August 1492, he set off from Spain with three ships     3     (carry) about 90 sailors. Regardless of many challenges he met with on the voyage, Columbus managed     4     (keep) everyone out of danger with his knowledge and bravery across the ocean and     5     (final), on 12 October, people on the ships     6     (spot) land in the distance. Columbus called the natives living on the islands Indians because he believed that he was in the East Indies,     7     actually the place they had reached was America.

Between 1493 and 1504, Columbus found more land later. His major     8     (contribute) is that he “discovered” the New World and     9     (he) discovery encouraged explorers such as Captain James Cook to explore and discover more vast areas of the world. His voyages opened     10     new chapter of the Age of Exploration, a period which saw many important geographical findings. This period also allowed for an international exchange of ideas and cultures.

2 . Many people today think of the pyramids of Giza as the symbol of ancient Egyptian culture. But who actually built them? For years, we did not know for sure. Now, however, archaeologists have discovered an ancient city near the pyramids. Close by, there is a cemetery (墓地) where the pyramid builders were buried. From studying these places, archaeologists are sure that the pyramids were not built by slaves or foreigners.    1    

It took about 80 years to build the pyramids. Archaeologists believe that about 20,000-30,000 people took part in the construction.     2     Some dug up the rock, some moved it, and some shaped it into blocks. People also worked on different teams, each with its own name. Workers often competed to see whose team could do a job faster.

“We can see that in their skeletons(骨骼),” says Azza Mohamed Sarry El-Din, a scientist studying bones found in the cemetery. According to her research, the bones show signs of arthritis (关节炎)．    3     Archaeologists have also found many female skeletons in the ancient city and cemetery. The damage to their bones is similar to that of the men.    4     Male workers generally lived to age 40-45, but women to only 30-35. However, workers usually had enough food, and they also received medical care if they got sick or hurt.

    5     On a wall in Khufu's Great Pyramid, for example, a group of workers wrote Friends of Khufu. “It's because they were not just building the tomb of their king,” says Egyptian archaeologist Zahi Hawass. “They were building Egypt. It was a national project, and everyone was a part.”