Suffix -ed / -en (participle) in English

The participle can also be irregular, as in ill-gotten, from get.

Adverb + participle (the form in have chosen or have known). The hyphen depends on the adverb:

• well + knowngivesa well-known actorwell, ill, better, best: hyphen before the noun
  • ill + timedgivesan ill-timed question
• highly + paidgivesa highly paid job-ly adverb: never a hyphen
• soft + spokengivessoft-spokenother short adverbs (soft, high, deep): hyphenated, as the dictionary lists them
  • deep + rootedgivesdeep-rooted

After the verb, the Chicago Manual of Style drops the hyphen (the actor is well known), but newspapers often keep it: both are accepted.

• well-chosen

  Her well-chosen words calmed everyone down.

• ill-defined

  The project failed because of its ill-defined goals.

• well-dressed

  A well-dressed man asked me for directions.

• ill-timed

  His ill-timed question interrupted the ceremony.

• well-kept

  They live in a well-kept house near the park.

• well-read

  My grandfather was a well-read man who loved history.

• well-founded

  They had well-founded doubts about the plan.

• soft-spoken

  The new teacher is soft-spoken but very clear.

• high-strung

  Her high-strung dog barks at every noise.

• deep-rooted

  His deep-rooted fear of dogs started when he was a kid.