-er eee eeo eer eet eo- eoe eoo eor eot ere ero err ert ete eto etr ett oee oeo oer oet oo- ooo oor oot or- ore oro orr ort ot- ote oto otr ott re- ree reo rer ret roe roo ror rot rrr rrt rte rto rtr rtt te- tee teo ter tet to- toe too tor tot tre tro trr trt tte tto ttr ttt

eeee eero eete eore eoto erer eret eroe eroo erre erro etee eter etoe etre etro ette etto o-eo oere ooer oooo oore oort ore- oreo orer oro- oroe oror orot orro orte orto otee oter oto- otoe otoo otor otre otro otte otto reet reot rere rero rert rete reto retr rett roer roet roor root rore roro rort rote roto rotr rott rrrr rtee teer teet teor ter- tere tero terr tete teto tetr tett toee toer toet toor toot tore toro torr tort tote toto totr tott tre- tree treo tret troe troo trot trte trtr tteo tter ttoe tttt

-tree eeeee eorre erere eroor erore eroto error erte erter etete etoro etree etter oo-er ooooo oreo- orere orero oroer orret orter ortet ortoo otere otero ototo otter reere rere- reree reret retee reter retro rette retto ro-ro roero rooer roore roote rorer roter roto- rotor rotot rotte rotto teret teror terre terro tert- teter tetr- tetro tette toerr toeto toore toreo toret torre torro torte torto toter toto- totoe totoo totte treer treet trere trete trett troee trott ttttt

eototo eroto- errett etoeot ettore oerter oooooo ottoor r-tree reroot reteer reteet reteoo retere retore retort retree retret retro- retrot retter rooter rootte rorter rotter t-tree teetee teeter terete terreo terrer terret terror terrot terter tertre tetete tetter toetoe tooter tootoo torero tororo torret tortor totoro totrot totter treete tretee trette trotro trotte

eeeroer ottetto ottrott reteere reterre retrete rettert rettore rootrot terere tereto- terreer terrere tettete toe-toe too-too torrert tototoo treetee trettre tro-tro trottee trotter

retorter teetoter toetotoe toottoot torotoro totterer treeroot

retrotort rotrooter

rotorooter toe-to-toe

roto-rooter

teetertotter

teeter-totter tetter-totter