帮我看看下面的一段英文有什么语法毛病啊?
Lastsummer,IhadachancetogotoBeijingasavolunteerfor2008Olympicgame.Thatactivitygavemeavaluablelessonformylife.Myjobwashelpingthosepeoplefromallovertheworldhowtogettheplacewheretheywanttogo.Atfirst,Ifeltalittlenervous.Butafterthreedayslatter,Icouldfeelmorecomfortable.Althoughthetaskwasveryhard,actually,therewerestillalotoffunduringthosedays.ThisactivityprovidesmeanopportunitytopracticemyEnglish,andimprovemycommunicationskillswithdifferentpeople.Olympicgameisagreateventforeveryoneintheworld.Lastsummer,whenIstandingonthelandofBeijing,itismygreathonortoseethismarvelouseventduringmylife,Iwillneverforgetthatmemorableexperience.