Aardvark and eel are words. They begin with double letters.
accessoryaddressaggressiveannuallyappallassessassassinbitternessbuccaneerblurrinessbulletproofbutterballbuttresscassettecarelessnesscarryallcoffeecommissarycommissioncrabbinessfurrinesshappinesspennilesspuffinessruddinesssluggishnessstiffnessstillnessstubbornnessstuffinesssuccesstallnessvolleyballwellnesswheelbarrow
Raccoon is a word. It includes double letters in a row.
addassallillofferrbeeseefeepeeteeweezooboocoogoomootoooddebb
accessaccommodationsbrassinessbeefinessembarrasscoffeechildlessnesscarelessnesscoolnesscheerfullycrisscrossclasslesscommitteecommittedfussinessfootlessfearlessnessfootloosefoolishnesshellishnesshopelessnessheaddresshappinessjoblessnesslawlessnessmoonlessmessinesspuffinessprissinesspeevishnesspennilessraccoonruthlessnesssuccesssleeplesssloppinesssleevelessspookinessstuffinessstiffnessspeechlesssillinessscruffinesstoothlesstattootoffee
Aardvark and eel are words. They begin with double letters.
accessoryaddressaggressiveannuallyappallassessassassinbitternessbuccaneerblurrinessbulletproofbutterballbuttresscassettecarelessnesscarryallcoffeecommissarycommissioncrabbinessfurrinesshappinesspennilesspuffinessruddinesssluggishnessstiffnessstillnessstubbornnessstuffinesssuccesstallnessvolleyballwellnesswheelbarrow
Raccoon is a word. It includes double letters in a row.
This question makes no sense. There are MANY words in which the letters are not followed by k. For instance, most of the words in this answer.
accentappreciatebannerbattleberrybetterbottlebuttercattlecrabbycuddledessertdribbleefficientetiquetteflabbyflannelfluttergabbyguzzlehammerhappyillinnovationjabberjugglekettleladderlessonmissilemufflenarrowoccuroddpatternpebblepoppypuppypuffyquarrysitterstaffstiffstubbornsummersuppertasseltoffeetunneluselessuttervacuumwafflewiggleyellowzipper
Words that have double letters, such as "door" or "glass," can pass through a green glass door.
Llama
addassallillofferrbeeseefeepeeteeweezooboocoogoomootoooddebb
baddestbiggesthottestfattestfittestflattestgladdestglibbestgrimmestmaddestsaddestslimmestsmuggestthinnesttrimmest
accessaccommodationsbrassinessbeefinessembarrasscoffeechildlessnesscarelessnesscoolnesscheerfullycrisscrossclasslesscommitteecommittedfussinessfootlessfearlessnessfootloosefoolishnesshellishnesshopelessnessheaddresshappinessjoblessnesslawlessnessmoonlessmessinesspuffinessprissinesspeevishnesspennilessraccoonruthlessnesssuccesssleeplesssloppinesssleevelessspookinessstuffinessstiffnessspeechlesssillinessscruffinesstoothlesstattootoffee
successfully
fettuccinehiccuppingoccurrencesuccessfulsuccessive