D
Skyscrapers and domed stadiums can amaze us. These modern “wonders of the world” are great achievements in building. Some skyscrapers stretch more than 100 stories toward the sky. The Sears Tower, the tallest building in Chicago, soars 110 stories above the city. Domed stadiums like the Astrodome in Huston, Texas, have seats for thousands of people. Inside these stadiums, people can watch their favorite sports without the bother of heat, cold, rain, or snow. Modern skyscrapers and domed stadiums are certainly marvelous structures!
On the other hand, our modern buildings may seem small when compared to some structures of the ancient world. Our buildings may be large, hold many people, and protect us from the weather. However, many ancient structures stand as some of the greatest achievements in building. Ancient builders used great creativity and physical strength to plan and complete these buildings. Today, we could make most of these ancient structures easily, but it is hard to understand ho
w people built them hundreds and hundreds of years ago.
Stonehenge is a huge stone circle in Europe. It was built more than 4,000 years ago. The circle has stone slabs that stand up to 30 feet tall. The heaviest stones in the circle weigh about 50 tons. How did people build Stonehenge without cranes or other modern equipment? Scientists have studied Stonehenge for years and think it probably took more than 30 million hours to complete the project.
Tourists in Africa like to see the Great Pyramids of Egypt. These tombs for Egyptian kings were 
built over 4,000 years ago. Each tomb has walls shaped like triangles and a square base. The largest pyramid is more than 450 feet tall and contains more than two million stones. Each stone weighs more than two tons. Some of the stones weigh as much as 200 tons. More than 900 workers worked to move the largest stones into place.
The stone faces are unusual structures on Easter Island. The faces are 12 to 20 feet high. Islanders made the stone faces more than 1,000 years ago. We do not know why they built them. There are more than 600 stone faces on the island. The great number of stone faces is surprising, since Easter Island is only 11 miles long and 15 miles wide.
Stonehenge, the Great Pyramids, and the stone faces on Easter Island give only a glimpse of the ancient achievements in building. If we look back through history, we can find many more examples of marvelous structures built without the aid of modern tools and equipment.
68．What is the main idea of this passage?
A．Modern builders have learned a great deal by studying ancient structures.
B．Modern builders have shown great creativity in the structures they have made.
C．Ancient builders could not create structures as great as modern ones.
D．Ancient builders created some of the world’s finest structures without the use of the modern methods or materials.
69．According to the passage, ancient structures are amazing because they were built ______ .
A．in places like Egypt and Europe B．without the use of modern equipment
C．from stone slabs D．over long periods of time
70．The author of this passage would probably describe the achievements of ancient builders as _____.
A．ordinary B．amazing C．strange D．impossible
71．Which of the following is an OPINION expressed in this pas
sage?
A．The stone slabs at Stonehenge stand up to 30 feet tall.
B．Modern skyscrapers and domed stadiums are certainly marvelous structures.
C．Some ancient structures required 900 workers to complete them.
D．The Sears Tower is 110 stories high.
