WEIRD PAST TENSE FORMS

It is often assumed that children go through a stage in which they sys tematically overapply irregular past tense patterns to inappropriate v erbs, as in wipe-wope, bring-brang, trick-truck, walk-has walken. Such errors have been interpreted both as reflecting over-use of minor gra mmatical rules (e.g. 'change i to a'), and as reflecting the operation of a connectionist pattern associator network that superimposes and b lends patterns of various degrees of generality. But the actual rate, time course, and nature of these errors have never been documented. We analysed 20,000 past tense and participle usages from nine children i n the CHILDES database, looking for overapplications of irregular vowe l-change patterns, as in brang, blends, as in branged, productive suff ixations of -en, as in walken, gross distortions, as in mail-membled, and double-suffixation, as in walkeded. These errors were collectively quite rare; children made them in about two tenths of one per cent of the opportunities, and with few stable patterns: the errors were not predominantly word-substitutions, did not occur predominantly with irr egular stems, showed no consistency across verbs or ages, and showed n o clear age trend. Most (though not all) of the errors were based clos ely on existing irregular verbs; gross distortions never occurred. We suggest that both rule-theories and connectionist theories have tended to overestimate the predominance of such errors. Children master irre gular forms quite accurately, presumably because irregular forms are j ust a special case of the arbitrary sound-meaning pairings that define words, and because children are good at learning words.