回答题：Directions:There are 20 blan

回答题：

Directions:There are 20 blanks in the following passage, and for each blank there are 4 choices marked A, B, C and D at the end of the passage. You should choose ONE answer that best fits into the passage. Then mark the corresponding letter on the Answer Sheet with a single line through the center.

Most young people enjoy physical activities, walking, cycling, football, or mountaineering.

These who have a passion56climbing high and difficult mountains are often57with

astonishment. Why are men and women58to suffer cold and hardship, and to59on
high mountains? This astonishment is caused, probably, by the difference between mountaineer-ing and other forms of activities60which men give their leisure. There are no man-made rules, as there are for61games as golf and football.
If we65mountaineering with other more familiar sports, we might think that one big
difference is66mountaineering is not a "team work". However, it is only our misunder-standing. There are, in fact, no" matches"67"teams" of climbers, but when climbers are on a rock face linked by a rope on which their lives may68, obviously, there is tea
A mountain climber knows that he may have to fight with natural69that are stronger and more powerful than man. His sport requires high mental and70qualities.
A mountain climber71to improve on skill year after year. A skier is probably past his best by the age of thirty, and most international tennis champions72in their early twenties.
But it is not73for men of fifty or sixty to climb the highest mountains in the Alps. They may take more74than younger men, but they probably climb with more skill and less75of effort, and they certainly experience equal enjoyment. 材
A.for
B.in
C.to
D.of