sullivan@harvard.ARPA (John Sullivan) (08/10/84)
The rule I learned, which seems to apply almost all the time, is that the
final consonant in a verb is doubled when forming the past tense only if
that final syllable is accented. Thus "canceled" has just one 'l' (although
I must admit it looks strange to me, and recently when I used it I had to
look it up to assure myself it wasn't an exception), while a word like
"rebelled" gets a second 'l'. I don't know of any exceptions to the rule
off hand.
John M. Sullivan
sullivan@harvard.{uucp,arpa}