During the Second World War, it was difficult to travel by plane, because the seats were needed for important government officials and army officers. Mr Brown worked for the government during the war and he was doing very secret work. Nobody was allowed to know how important he was except very few people. One day he had to fly to London to give a talk to a few top people there, but an important army officer came to the airport at the last minute. Mr Brown’s seat was given to him, so he was not able to fly to the city to give his talk.  When the important army officer reached the city , he found  that the man whose seat he had taken was the one whose talk he had flown to hear. 1.Mr Brown was ___________. A．an army officer                      B．a bad speaker C．a government official              D．a public speaker 2.Plane tickets were hard to get for _________. A．ordinary people              B．government officials C．army officers                 D．secret workers 3.Mr Brown could not take the plane, because _________. A．his secret work was discovered. B．he wanted to change for another plane. C．his seat was given to an important army officer. D．he was unable to go by air. 4.What did the army officer discover in the end? ________. A．He had taken a very important person’s seat. B．Mr Brown’s talk was important C．Mr Brown didn’t do important secret work D．Mr Brown was a kind person.