Wilbur Wright （萊特） was born in Millville，Indiana，in 1867．Orville was born in Dayton，Ohio，in 1871．They left school in high school，but they're interested in mechanical （機械的） things．They taught themselves math and engineering．
The Wrights became interested in the work of German inventor Otto Lilienthal．Lilienthal designed （設計） and flew on gliders （滑翔機）．Lilienthal died in a glider accident in 1896．So the brothers decided to build a flying machine and learn how to control （控制） flight safely．
After many experiments，the Wright brothers invented the first safe，successful airplane．But their first flight-Flyer I，on December 17，1903，was not great news．Nothing appeared in the newspaper on that day．A few days later，short reports began to appear in newspapers across the country，but no one seemed very interested．
Orville Wright took the"Flyer I"up in the air．It lasted for 12 seconds．Wilbur Wright took turns with his brother flying their airplane．The next two flights each lasted twice as long as the first one．On the fourth flight that day，the airplane stayed in the air for 59 seconds．After it landed，a sudden wind tipped （翻到） the plane over．"Flyer I"was badly destroyed．The first successful airplane was never flown again．But those 12 seconds changed history．

76．How did Wright brothers learn math after they left school？

They taught themselves math．/They learned math by themselves．/By teaching themselves．

They taught themselves math．/They learned math by themselves．/By teaching themselves．

77．What did the Wright brothers decide to do after Lilienthal's death？

They decided to build a flying machine and learn how to control flight safely．

They decided to build a flying machine and learn how to control flight safely．

78．When did they first fly their airplane？

On December 17，1903．

On December 17，1903．

79．Did their first flight get much attention at that time？

No．/No，it didn't．

No．/No，it didn't．

80．How long did the first flight last？

It lasted for 12 seconds．/For 12 seconds．

It lasted for 12 seconds．/For 12 seconds．

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