This study investigated the use of stative, process, punctual, and non-punctual verbs by a child acquiring Japanese as a first language between the ages of 1;0 and 4;11 in an attempt to find evidence for two of Bickerton's (1981) proposed language acquisition universals, which form part of the language bioprogram hypothesis of language acquisition. As predicted by Bickerton's state-process hypothesis, it was found that all sampled present progressive verb forms occurred with process verbs while these forms were never used with stative verbs. Also, with only one exception, all omissions of present progressive forms occurred with the early use of ‘mixed’ verbs, i.e. verbs which behave syntactically as process verbs in Japanese but are nonetheless semantically stative. However, contrasting with Bickerton's hypothesis that children initially use the past tense to mark punctuality, no relationship between past tense use and punctuality was found.