I've been thinking of the Omaha-Ponca 'suddenly' verbs as inceptive/punctuals, but the more I ponder Randy's 'unexpected' idea, the more it seems to me that I might be missing a possibility. 'Unexpected' does correlate fairly well with 'begin, become' in terms of 'novelty'. I'll look at the examples and see if I can tell which approach works better. JEK