None, there is no such letters in the English language.
Some words containing k, g, w:knowingtweakingwakingwalkingwhackingwinking
4 Letter Scrabble Wordsdampdarkdrammarkpardparkpramramp3 Letter Scrabble Wordsamparkarmdakdamdapmadmapmarpadpamparradramrap2 Letter Scrabble Wordsadamarkamapa
Bookkeeper and jackknife are words. They contain the letters kk.
fog, keg, feik, and of are all i can think of...
vikingskivingknaveskiveskivedevokeevokedevokes
wake
Some words containing k, g, w:knowingtweakingwakingwalkingwhackingwinking
4 Letter Scrabble Wordsdampdarkdrammarkpardparkpramramp3 Letter Scrabble Wordsamparkarmdakdamdapmadmapmarpadpamparradramrap2 Letter Scrabble Wordsadamarkamapa
invoke
Bookkeeper and jackknife are words. They contain the letters kk.
Scrabble words using the letters A N K A E T U C: * tank * tuck * tack * teak * cute * cane * knack * case * cute
Back, berk, Brok, beak, beck, book, break, brook,
Buckle, Bucket, Ruckus, Sucker, Bucked, Flukes...
The letters c e k o p t can be rearranged to make the word pocket.
big gab bag wag wig
Flosh
fog, keg, feik, and of are all i can think of...