Unidentified Flying Object
Unidentified Flying Object is any object or light, reportedly sighted in the sky, that cannot be immediately explained by the observer. Sightings of unusual flying objects date back to ancient times, but UFOs became widely discussed only after the first widely publicized U.S. sighting in 1947. Many thousands of such observations have since been reported worldwide.
At least 90 percent of UFO sightings can be identified as conventional objects, although time-consuming investigations are often necessary for such identification. The objects most often mistaken for UFOs are bright planets and stars, aircraft, birds, balloons, kites, aerial flares, peculiar clouds , meteors, and satellites. The remaining sightings most likely can be attributed to other mistaken sightings or to inaccurate reporting, tricks, or delusions, although to disprove all claims made about UFOs is impossible.
From 1947 to 1969 the U.S. Air Force investigated UFOs as a possible threat to national security. A total of 12,618 reports were received, of which 701 reports, or 5.6 percent, were listed as unexplained. The air force concluded that no UFO reported, investigated, and evaluated by the Air Force has ever given any indication of threat to our national security. Since 1969 no agency of the U.S. government has had any active program of UFO investigation.
Some persons, however, believe that UFOs are extraterrestrial spacecraft, even though no scientifically valid evidence supports that belief. The possibility of extraterrestrial civilizations is not the stumbling block; most scientists grant that intelligent life may well exist elsewhere in the universe. A fully convincing UFO photograph has yet to be taken, however, and the scientific method requires that highly speculative explanations should not be adopted unless all of the more ordinary explanations can be ruled out.
Called Maglev for short, the system under discussion makes use of a high-speed train levitated above a guideway and propelled by magnetic fields. The project has been in the talking stage for several months.
Hans Ueberschaer, Germans ambassador visited the city together with Harmut Heine, representative of Thyssen Krupp. They had an initial discussion with the mayor there about the prospect of the project. The talks were believed to be constructive and paved the way for the future talks in Berlin, where a commitment was reached.
Sources familiar with the talks estimated that the project would cost US$723 million, which would cover everything from land use fees and rail construction to train cars. Completion date is 2005. A joint venture company is to be established for the project.
1. Who paved the way for further negotiations in Berlin?
A) The mayor
B) Both the German ambassador and the mayor.
C) The German ambassador.
D) The representative from the German company.
2. What was the signed commitment mainly about?
A) Finalizing the payment of US$723 million.
B) Establishing a joint venture company.
C) Conducting a feasibility study.
D) Outlining the German companys intention to export its technology.
3. What is the main feature of Maglev?
A) The Maglev train floats above the guideway and zip to its destination.
B) The Maglev train zips to its destination on the railway.
C) The Maglev train zips to its destination on a double guideway.
D) The Maglev train can carry more passengers than the electric train.
4. How large will be the success rate of the agreement signed by the two business parties according to the passage?
A) It is very likely that the city will have a German-built Maglev line.
B) It is very likely that Krupp will ban the export of its technology.
C) It is very likely that the city cannot afford the high payment.
D) It is very likely that the city will turn to buy US technology.
5. What type of writing do you think this passage belongs to?
A) An article on popular science.
B) An article taken from a transportation book.
C) A commercial contract.
D) A news report.
答案: B C A A D
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