bbb bbi bbk bbs bbt bi- bib bii bik bis bit bkb bkk bks bkt bsb bsi bsk bss bst btb bti btk bts btt ibb ibi ibk ibs ibt iib iii iis iit ikb iki ikk iks ikt is- isb isi isk iss ist itb iti itk its itt k-t kbb kbi kbk kbs kib kii kik kis kit kkb kki kkk kks kkt ksb ksi ksk kss kst ktb ktk kts ktt sbb sbi sbk sbs sbt sib sii sik sis sit sk- skb ski skk sks skt ss- ssb ssi ssk sss sst stb sti stk sts stt tbb tbi tbk tbs tbt tib tii tik tis tit tkb tkk tks tkt tsb tsi tsk tss tst ttb tti ttk tts ttt