用所给动词的适当时态填空.
George______(be)inbusinesssincehegraduatedfromcollage.
We______(learn)threethousandEnglishwordsbytheendoflastterm.
Thesheep______(disappear)oneafteranothersincelastmonth.
TheOlmpicGames______(take)placetwenty-ninetinessince1896.
MrLididn'tgotothecinemabecausehe______(see)thefilmbrfore.
Thegovernment______(make)trafficlawstostopaccidentsrecently.
I______(read)TheAdventurESofTomSawyerthesedays.
Don'tworry.Thework______(finish)already.
Peter'smother______(tell)thatherson______(apologize)toMrBrownalreadyforbreakinghiswindow.