单项选择题
判断题 In his traveling experience, the man has been in hurricanes, tornados, seen tidal waves, volcanoes erupting, and been involved in a plane crash.
单项选择题 Which means of transportation will be the most important method of getting around in the twenty-first century
单项选择题 According to the article, in the twenty-first century an American businessman will spend less than ______ to go to Paris.