On May 5^th，2017， at Shanghai Pudong International Airport，China's first large homemade jet airliner（喷气式客机），the C919， took off successfully for the first time． It has taken about ten years for the scientists and researchers to make this Chinese dream come true．It s a pride of the whole nation． So far， more than 23 companies have already ordered 570 C919 planes from China． But we still have a long way to go before the C919 carries passengers by 2020．

     What's more， China is working on the new high﹣speed trains with the highest speed of 400km/h． It will be ready by 2020． Many countries， especially the ones in Central Asia， Southeast Asia， the Middle East and Eastern Europe， are planning to build high﹣speed rail lines or to improve their railways with the help of China．

     China has made great progress in both science and technology． And it makes a great contribution（贡献）to humans，too． All of these are changing the daily life of Chinese people， even of the people around the world．

（1）When did the C919 take off successfully for the first time？　　

（2）How long has it taken the scientists and researchers to make the C919？　　

（3）How many companies have already ordered 570 C919 planes from China？　　

（4）Are many countries planning to improve their railways with the help of China？　　

（5）What fields has China made great progress in according to the passage？