a-be aaaa aaab aaae aaar aaba aabb aaea aara aare abaa abab abae abar abb- abba abbb abbe abbr abee aber abra aeer aer- aera arab arae arar arba arbe area aree arr- arra arre arrr baaa baar baba babb babe babr baer bar- bara barb bare barr bbbb bbeb bear beba bebb bebe beeb beer bera bere berr brab brae brea breb bree brer brrr eaba eara earb eare ebba ebbr eber eeea eeee eera erba erbb erbe ereb erer erra erre raab raba rabb rabe raer rara rarb rare rbbb rbbr rea- reae rear reba rebb rebe reeb rera rere rrrr