I am confused

[cema]

Pay - paid, not payed
Play - played, not plaid

Is that a rule or an exception? (This being English, may not be that different.)

Comments

[cema.livejournal.com]

Yes, there must be plenty of such red words in English, and perhaps some of them may be grouped in rules. For others no useful rules may be found (or perhaps only trivial rules which cover one or two cases). Really, the difference between a rule and an exception may be murky.