狗DogsNowadaysmanypeopleliketohavedogsastheirpets.Dogsarefriendsofmannotonlybecausetheyarelovelybutalsobecausetheyarefaithfultotheirmasters.Dogscandoalotofworkforman.Theyplaywithus.Theyhuntwithus.Theykeepdoorforus.Butlongago,dogsallovertheworldwerewild.DogscandatebacktotheStoneAge.Alldogshavethesameancestor.Itisbelievedthattheirancestorwasmuchlikeawolf.Otheranimals,suchasthefox,camefromthisancestor,too.Hundredsofthousandsofyearsago,manbegantotamewilddogs.Afterthedogsweretamed,theyweretrained.Thestrongdogsbecameworkinganimals.Theyweretrainedtopullheavyloads.Theylearnedtokeepaneyeonthesheepandotheranimals.Workingdogshadotherjobs,too.Somedogswerenotstrong.Buttheycouldhelpmanhuntforgame.Otherdogswerebestaspets.Today,therearemorethan100kindsofdogsintheworld.1
