Read the following passage carefully and complete the succeeding three items I,II,IV.(1)Nazca (纳斯卡)is one of South America's most perplexing archaeological riddles and one of the world's most beautiful works of art. Etched upon Peru's vast,barren Nazca Plains are hundreds of long,ruler-straight lines, immense geometric symbols and giant drawings of curious birds and animals, the work of pre-Inca Peruvians 1,500 years ago.(2) Nazca was first revealed to modern eyes in 1926 when three explorers looked down on the desert from a hillside at dusk and briefly saw a Nazca line highlighted by the low slanting rays of the sun. But it was not until the Peruvian air force took aerial photographs in the 1940s that the full magnificence of the panorama was apparent.It was as if a dozen deserted airports were spread out across the plains.Hundreds of what looked like “landing strips”for aircraft were revealed.There were eighteen condor(秃 鹰)-like bird drawings,up to 400 feet long;four-sided figures with two lines parallel;and long needle-like triangles which ran for miles.Often the long lines met,like star-clusters.Among the many abstract patterns were a giant spider,a monkey,a shark,reptiles and flowers,all drawn on the ground on a huge scale(3) The scale is monumental,but from the ground almost invisible and totally incomprehensible. The amazing fact about Nazca,created more than 1,500 years ago,is that it can only be appreciated if seen from the air.Many, therefore,regarded it as a prehistoric landing ground for visitors from outer space,but Jim Woodman,an American explorer,who was long fascinated by the mystery of Nazca,was convinced that the ingenious ancient people of the area had learned to fly.He believed that Nazca only made sense if the people who had designed and made these vast drawings on the ground could actually see them,and that led him to the theory that the ancient Peruvians had somehow learned to fly,as only from above could they really see the extent of their handiwork.With this theory in mind,he researched into ancient Peruvian legends about flight and came to the conclusion that the only feasible answer was a hot-air balloon.To make such a balloon in the way the ancients must have done,Woodman learned that he would require four things: textiles,to make the bag to trap and hold the hot air;a power source like fire to heat the air;calm weather to allow the inflation of the balloon;and the intelligence to devise such a craft.(4)Peruvian mythology was full of ideas about flying.Ample evidence of this was found in the designs on Nazca pottery and tapestries and the art of ballooning survives today among primitive South American peoples.One of the theories about the balloons was that it was the way in which some Incas returned their dead to the gods—by hot-air balloons that soared out of sight towards the sun before prevailing winds a mile or more up wafted them out over the Pacific Ocean to sink unseen into the water as the air cooled at sunset.(5)Woodman built a balloon-type airship of the same fabrics and fibers that would have been available to the men of Nazca at the time. It was high adventure and culminated in the spectacular flight of a balloon which Woodman called“Condor I”. There was no doubt about it,only from the air could the full glory of Nazca be appreciated.“Flying between 300 and 1,000 feet,the sheer size,scope and beauty of Nazca is electrifying.Soaring above it all,I knew that ancient eyes had seen the immense creation below.Ancient man could never have built and devised all this and never seen it,”said Woodman.“If we,as‘modern men',could fashion a flying craft by using only cotton,hemp and fire,surely those who were there in Peru centuries before could have done the same.Everything necessary to fly was there.”Jim Woodman's flight was a modern demonstration of an ancient possibility.(6)His practical demonstration may have been spectacular,but Woodman had failed to impress the historic and scientific community.While not as outlandish as Erich von Däniken's extraterrestrial orientated Nazca theories, Woodman's hot air balloon concept is largely discredited. A large number of holes in Woodman's theory have been pointed out,many of which center upon his inconsistent and inexact supporting evidence. However,what Woodman accomplished with the Nazca hot air balloon was not without lasting merit. The successful though short-lived flight of Condor I raised some interesting questions about aviation history and the history of technological development as a whole. A large number of holes in Woodman's theory have been pointed out,many of which center upon his inconsistent and inexact supporting evidence.