Is this term an irregular verb where the past and past participle conjugations follow some odd rule?

A verb is irregular when the past and past participle conjugations are different.

Verb Conjugation Rules.

  1. Past tense: add –d, -ed, or –t to end of verb
    • For verbs ending in –y change –y to -i and add –ed
    • Examples: log – logged, bend – bent, lobby – lobbied
  2. Past participle: add -d or ed or –t to end of verb
    • For verbs ending in –y change –y to -i and add –ed
    • Examples: Examples: log – logged, bend – bent, lobby – lobbied
  3. Present Participle: add -ing to end of verb
    • For verbs ending in –e remove –e before adding –ing. This rule excludes verbs ending in –ee. Verbs ending in –ee follow normal convention of adding –ing to the end.
    • Examples: log – logging, brake – braking, flee – fleeing
  4. Third Person: add -s or -es to end of verb
    • For verbs ending in –y change –y to -i and add –es
    • Examples: log – logs, lobby – lobbies, catch – catches

Irregular Verb Examples

Verb Past Past Participle
arise arose  arisen
begin began  begun
catch caught  caught
do did  done
fall fell  fallen
go went  gone
hide hid  hidden
lay laid  laid
lie lay  lain