阅读理解. The year was 1985.Ronald Reagan was president.Mikhail Gorbachev became leader of the USSR. Back to the Future was boffo at the box office.'Born in the USA' was climbing the charts.Philanthropy (慈善业) and pop culture combined with LiveAid and 'We Are the World. ' And ' .com ', which few people outside of the military or universities knew,came into this world. Looking back,few could have predicted '.com' would become one of the biggest cultural touchstones of the century.In March 1985,the Information Sciences Institute at the University of Southern California assigned the first.com domain address to symbolics.com.That seemingly nominal (象征性的) event set into motion forces that would change our world forever. .com wasn't the birth of the Internet,but it was the budding computer network's comingout party.It made it pretty and inviting.It did away with the need to have complex 'maps' that were the equivalent of writing a phone number on your hand,and opened it up for a mainstream audience. After 1985,all it takes is a simple.com name to get into business.'.com' became part of our daily lexicon and  drove its own economic boom and depression. It helped create a whole new family of  industries, facilitated  global commerce and connected people around the world in ways never before possible. It's now 2010.Barack Obama is president,thanks in part to his smart use of the Internet.There is no USSR.A computergenerated Avatar has set new box office records.'TiK ToK' tops the charts.We're sending robots to find water on Mars.And that onceobscure computer communications system is one of our civilization's most prominent features. 1．This passage was written to mark________. A．the change of American presidency B．the development of entertainment C．the 25th anniversary of.com D．the anniversary of the internet 2．What does the underlined word 'boffo' probably mean? A．Successful. B．Changeable. C．Tough. D．Novel. 3．Which of the following can be the main contribution of '.com'? A．It gave birth to the Internet. B．It combined politics,entertainment and space science. C．It made the Internet accessible to ordinary people. D．It helped produce more domain addresses. 4．We can infer that before 1985,getting on line was________. A．impossible B．complex C．expensive D．popular 5．The first and last paragraphs were intended to________. A．make comparison B．provide details C．list arguments D．stimulate readers' interest