bbbb bbch bcbc bccc bctc bhcc bhot bobb bobo boch boco boho boht boob booc booh boot botb both boto bott btcc btob bttb c-bo cbbc cbcc cbct cbot cbtc ccbc cccb cccc ccob ccoc cctb cctc cctt chch choc choh choo chto chtt cobb cobh cobo coch coco coct coho coob cooh coot cotb cotc coth coto cott ctot hboc hcbc hccb hccc hcch hhhh hobo hoch hoho hoot hotb hoth hoto hott htcc htoh obbo obot ocbc occc occt ocht oct- octo ohcc ohho ohob ohoh ohto ooho oooh oooo ootb otho oto- otoh otoo otto tbcb tbcc tccc tch- tchh tcho tctc thch thoo thot thtb tobo tobt toch toco toho tooh toot totc toth toto tott ttbb tttt