Unit 1Fighting with the Forces of NatureOverview Theforcesofnaturecanplayadecisiveroleindeterminingtheoutcomeofawar.Severeweatherisoftenconsideredacurse,butforthosefacingattackitcancomeasablessing.Thetwostoriesinthisunitvividlyillustratethepowerofnaturetoshapethecourseofhistory.词汇变色 （1 ）-courseN.(1)Theplanewasoncourse.Heradioedthepilottochangecourse.(2)Thewisestcoursewouldbesaynothing.Therearevariouscoursesopentous. Theunexpectedcourseofeventsarousedconsiderablealarm.Changethecourseofhistory词汇变
