21.The USA makes a lot of excuses in an attempt to make war on Iran, however, its     purpose lies in the abundant oil there£®
A£®logical   B£®fundamental  C£®accurate   D£®common
22.After 1953 several hundred people have succeeded in climbing the mountain, some to be the first of their nation and many ______ to climb over different slopes.
    A. in charge         B. in attempts        C. in anxiety      D. in detail
23.Considering the complicated academic topic, try to       your speech in case it should go beyond the children.