A.the unsettledness of travel
B.the difficulties of trekking
C.the loneliness of travel
D.the unfamiliar environment
A.violated the traffic law.
B.illegally attacked a boxer.
C.attacked sB.after a traffic accident.
D.failed to finish his contract.
A.by the end of the year.
B.in over a year.
C.in August.
D.in a few weeks.
A.they cover the whole story of the former US president.
B.the assassin used to live in the former Soviet Union.
C.they are the only official documents released about Kennedy.
D.they solved the mystery surrounding Kennedy's assassination.