- happen
- open
- listen
- strengthen
- threaten
- tighten
- frighten
- weaken
- widen
- soften
- broaden
- lessen
- harden
- loosen
- screen
- straighten
- hasten
- shorten
- reopen
- sharpen
- deepen
- lighten
- brighten
- flatten
- fasten
- dampen
- worsen
- heighten
- lengthen
- enlighten
- darken
- stiffen
- ken
- ripen
- awaken
- quicken
- thicken
- quieten
- waken
- overburden
- fatten
- slacken
- even
- enliven
- sweeten
- chicken
- pen
- burden
- liken
- freshen
- yen
- moisten
- blacken
- handwritten
- toughen
- liven
- smarten
- preen
- unfasten
- redden
- glisten
- batten
- christen
- cheapen
- betoken
- deaden
- neaten
- hearken
- reawaken
- garden
- over-ridden
- deafen
- gladden
- tauten
- whiten
- haven
- leaven
- sadden
- steepen
- dishearten
- hearten
- keen
- overtighten
- shapen
- rewoven
- retighten
- refasten
- queen
- crispen
- shotten
- unwoven
- balden
- madden
- chasten
- copperfasten
- unhappen
- untighten
- remoisten
- foreshorten
- unburden
- hoven
- impen
- hen
- roughen
- scarcen
- spicen
- dizen
- pinken
- outken
- atren
- elden
- unhidden
- bescreen
- pseudolisten
- grossen
- badden
- mishappen
- safen
- ken
- nicen
- oversoften
- teen
- unsweeten
- teen
- slicken
- cruden
- drunken
- careen
- naken
- sleeken
- unforgiven
- embiggen
- illighten
- cozen
- leave one's options open
- choke the chicken
- dumben
- superharden
- engladden
- enrichen
- unforgotten
- ruden
- unsadden
- get even
- leave someone on seen
- righten
- beseen
- case harden
- relisten
- thwarten
- prewhiten
- sparken
- hang ten
- bemoisten
- enripen
- fraynen
- have a bun in the oven
- breadthen
- piecen
- rescreen
- mirken
- photowritten
- slaken
- bedizen
- die and go to heaven
- siren
- bedizzen
- enchasten
- highen
- bemoysten
- enlargen
- foretaken
- unmaiden
- disburden
- nighen
- unshorten
- taste like chicken
- peacen
- enlengthen
- dequeen
- rechristen
- requeen
- enlessen
- beken
- blissen
- overladen
- behappen
- disburthen
- green
- colden
- beshitten
- gladen
- heaven
- shoulder the burden
- descreen
- sleep with one eye open
- braven
- cuten
- ween
- ween
- forlighten
- ween
- break even
- lifen
- outen
- cry craven
- fruiten
- blanken
- glassen
- filsten
- barken
- unseen
- mispen
- shitten
- copper fasten
- back-sweeten
- bluen
- laxen
- reloosen
- harshen
- requicken
- embolden
- freaken
- lippen
- omen
- unwritten
- caseharden
- underbitten
- spiriten
- foretoken
- nerven
- blunten
- ghosten
- bursten
- keen
- overween
- think of the children
- overripen
- copper-fasten
- cosen
- sitten
- know someone when
- prescreen
- unchristen
- sitten
- hoiden
- benighten
- wasten
- hotten
- slighten
- come between
- blithen
- wetten
- downtrodden
- harten
- ungladden
- steven
- borken
- relengthen
- enmilden
- sken
- preen
- steven
- stricten
- neven
- stouten
- burthen
- rehappen
- besweeten
- reharden
- filthen
- craven
- betrodden
- overleaven
- greyen
- have drink taken
- endarken
- hyphen
- closen
- falsen
- locken
- underween
- aken
- forshorten
- restraighten
- aken
- unflatten
- blicken
- overlengthen
- straiten
- enfasten
- basen
- gooden
- refatten
- sicken
- frosten
- bleaken
- gooden
- overharden
- misken
- coosen
- forshrunken
- steen
- halsen
- behearken
- liven
- sparsen
- kitten
- raven
- engolden
- blonden
- keep a weather eye open
- largen
- goose-pen
- remain to be seen
- tween
- unpen
- meeken
- hoarsen
- compensatorily lengthen
- undarken
- unharden
- keep an eye open
- limpen
- misween
- crooken
- unliken
- soothen
- mischristen
- gilden
- bliken
- grayen
- restrengthen
- outspoken
- daven
- swidden
- can't even
- forehalsen
- overscreen
- swarten
- call it even
- encolden
- lien
- healthen
- leven
- downfallen
- presweeten
- foreshorten
- forewritten
- forspoken
- golden
- ensmallen
- lanken
- poshen
- starken
- shapen
- slocken
- neshen
- brazen
- denizen
- lay open
- streighten
- costen
- waxen
- hammer-harden
- platten
- twilitten
- greaten
- get open
- laten
- afterseen
- enweaken
- boughten
- affrighten
- infallen
- enwiden
- outpreen
- fucken
- deredden
- ywroken
- enwisen
- disemburden
- olden
- coolen
- unstiffen
- embrighten
- engraven
- undeafen
- breakeven
- engraven
- premoisten
- tarten
- whetten
- mislippen
- vent one's spleen
- den
- engreaten
- besotten
- engreen
- milden
- flick open
- oversweeten
- queazen
- have one's name taken
- meeten
- louden
- token
- outbrazen
- say when
- washen
- enstraighten
- enstraiten
- fretten
- endenizen
- enstrengthen
- dullen
- unqueen
- salten
- fiercen
- keep one's options open
- stink to high heaven
- regen
- biggen
- unseven
- biggen
- regreen
- preharden
- disliken
- retrogreen
- outsweeten
- amen
- rewaken
- peen
- sodden
- instrengthen
- bedarken
- overburthen
- spleen
- querken
- warden
- inlighten
- ensweeten
- wizen
- truthen
- prelisten
- lushen
- resoften
- flehmen
- wisen
- richen
- foreken
- outgreen
- overthicken
- imbolden
- oversharpen
- unburthen
- bewritten
- shagreen
- writhen
- forespoken
- fainten
- crack open
- unladen
- deharden
- skreen
- spoil somebody rotten
- blinden
- disquieten
- dusken
- endizen
- enharden
- count to ten
- brassen
- parcen
- danken
- gracen
- plumpen
- outredden
- sheen
- silken
- gen
- gloppen
- streaken
- gen
- letten
- worthen
- heaten
- begladden
- worthen
- hoyden
- pen
- unshaken
- unstraighten
- enhearten
- bluescreen
- beglisten
- bowssen
- sewen
- alien
- feen
- unscreen
- densen
- draw even
- resharpen
- rewetten
- bedeafen
- bren
- silkscreen
- blooden
- unloosen
- damaskeen
- bolden
- rewiden
- damasken
- brisken
- taughten
- refreshen
- rethicken
- taughten
- flighten
- unshapen
- holpen
- rough up the bullpen
- palen
- unsharpen
- evergreen
- ratten
- enquicken
- batten
- smoothen
- youthen
- emburden
- indenizen
- windscreen
- leaden
- rudden
- coarsen
- kaizen
- forharden
- gleen
- beard the lion in his den
- harken
- shiten
- unspoken
Note: these words have been obtained from Wiktionary and have been classified and improved through automated computer linguistics processes.