The highest mountain in the world is Mount Everest．It is about 8．9 kilometers above sea level．Many men have tried to climb this mountain but without success．High winds, cold and little oxygen have made this almost an impossible thing．It was not until 1953 that two men stood on the top．One of the men was Edmund Hillary from New Zealand．The other was Tenzing of Nepal．They were members of a British Expedition(探險(xiǎn)隊(duì))．There were nearly twenty people in the whole team．They spent about sixty days to finish the whole climbing．The last day, May 29^th, was fine．Hillary and Tenzing started climbing as the sun rose． At half past eleven they were on top of Mount Everest．They were very glad．They wanted to stay there for some time, but they couldn’t．It was too cold and dangerous． They had climbed as high as anyone can climb----- they were on top of the world．

1．When did people first climb up to the top of the world?

A．Never．                                       B．On May 29^th, 1954．

C．One day in 1953．                               D．Nearly 60 days after May 29^th, 1953．

2．________can make climbing Mount Everest very difficult?

A．High clouds, cold and little oxygen             B．No cars and no planes

C．Few people                                D．Winds, cold and oxygen

3．Who climbed up to the top of the world first?

A．British people．                         B．A expedition．

C．A New Zealand person and a Nepal person．  D．None．

4．How high is the top of the world?

A．No one knows．                             B．9．8 kilometers．

C．8900 meters．                               D．Above the sea level．