抄録
In this paper I analyzed several phenomena of presumed linguistic change using the minutes of the National Diet of Japan since 1947, particularly in terms of the relationship between the speaker's birth year and the time when an utterance was produced. In many cases, the data show apparent changes through the lifetimes of the speakers of the same birth decade. The phenomena discussed include the choice of na/no as suffixes for the form ‘X-teki', the choice of aru/iru as verbs in existential sentences with a human subject, the co-occurrence relations between the adverbs zenzen/mattaku and negative morphemes, the choice of iru/oru as auxiliary verbs, and the preservation of the archaic form masuru.