Fill in the blanks with correct tense.1．During the last 100 years,humans ________(go)[1] from walking on Earth to walking on the moon.They __________ (go) [2] from riding horses to flying jet airplanes.With each decade,aviation technology _________(cross)[3] another frontier,and,with each crossing,the world _________(change)[4].During the 20th century,five companies ___________(chart)[5] the course of aerospace history in the United States.They_______

Fill in the blanks with correct tense.
1．During the last 100 years,humans ________(go)[1] from walking on Earth to walking on the moon.They __________ (go) [2] from riding horses to flying jet airplanes.With each decade,aviation technology _________(cross)[3] another frontier,and,with each crossing,the world _________(change)[4].
During the 20th century,five companies ___________(chart)[5] the course of aerospace history in the United States.They__________(be) [6] the Boeing Airplane Co.,Douglas Aircraft Co.,McDonnell Aircraft Corp.,North American Aviation and Hughes Aircraft.By the dawning of the new millennium,they ________ (join) [7] forces to share a legacy of victory and discovery,cooperation and competition,high adventure and hard struggle.
Their stories _________(begin) [8] with five men who ______(share) [9] the vision that ______(give)[10] tangible wings to the eternal dream of flight.William Edward Boeing,born in 1881 in Detroit,Mich.,began building floatplanes near Seattle,Wash.Donald Wills Douglas,born in 1892 in New York,began building bombers and passenger transports in Santa Monica,Calif.James Smith McDonnell,born in 1899 in Denver,Colo.,began building jet fighters in St.Louis,Mo.James Howard "Dutch" Kindelberger,born in 1895 in Wheeling,W.Va.,began building trainers in Los Angeles,Calif.Howard Hughes Jr.was born in Houston,Texas,in 1905.The Hughes Space and Communications Co.built the world's first geosynchronous communications satellite in 1963.
The companies began their journey across the frontiers of aerospace at different times and under different circumstances.Their paths merged and their contributions are the common heritage of The Boeing Company today.
2.From the earliest days after its foundation in 1872,Zurich _________ (start)[1] to expand outside the borders of Switzerland.Within the first eight years,we _______(have)[2] become an international business.Today,Zurich _____ (have)[3] a strong foothold on both sides of the Atlantic and a significant presence in other world markets.
Innovation has always been a driving force.In 1898,Zurich ________ _(pioneer)[4]auto insurance when its Belgian branch office ____________(publish)[5] the first rate schedule.Zurich was the first insurer to offer global programs in its home country,and in 1912 _________(become)[6] the first European insurance company in the United States.
Ten years later,the Vita Life Insurance Company ________(found)[7] in Switzerland,and in 1925,Vita ________(become)[8]the first European insurer to offer free medical check-ups to customers.In 1994 Zurich ________(be)[9] the first insurer to introduce direct telephone marketing to the Swiss market.Three years later,HelpPoints _________( introduce)[10] in Switzerland,where customers can arrange for damage to their car or home to be repaired quickly and claims settled expeditiously.This innovative idea was successfully “exported” to Farmers in the US.