Itwasmy18thbirthdayyesterday.Astheageisspecialforour(us) us与teenagers是同位语teenagers,so(去掉so)此处为主句myparentsheldabirthdaypartyformeathome.Withmyparentsandsomeofmygoodfriendsattend(attending)此处作状语，用在with后，用doingmybirthdayparty,Ireallyhad(加an)experience此处指的是经历，可数名词unforgettableexperience.Wesangsongs,dancing(danced)作并列谓语，andplayedgamestogether.Weallenjoyedourselvesverymuch.Duringtheparty,myparent(parents)父母是两个人，要选用复数toldmethatfromthenonIwasnolongerachildand(but)not..but结构，意为我不再是一个孩子了，而是一个大人了anadult.TheyalsosaidIshouldbemoreindependentandresponsibly(responsible)此处与independent是并列关系，作表语.Hearingtheirwords,Iwasgreatlyencouraged.Itwasjustin(at)常用搭配thatmomentwhen(that)强调句IfeltIwasagrown-up.]

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