b-tree bbbbbb beebee beebem beembe beemer beerme beeter bemeet bemete berbee berber bereet berere bermet berrer berret bertem bertre beteem betere betete bettee better breere bremer brette ceecee cerete cermet creete cremec cremer ebbert eebree eerect embree emeere emeter emmert emmett erbree errett etcetc m-tree mbembe mccree mcteer meeter meetme meetre member membre mememe memere mercer merece merete mermer mermet merrem merret merter meteer metrer metter mettet r-tree rebbec remeet remete retece reteer reteet retere reterm retree retret retter t-tree teebee teemer teerme teetee teeter tembec tembre temere tercer tercet terete termer terrer terret terter tertre tetete tetter tr-rec trebce treece treete tremet tretee trette