This article employs the ‘multiple grammars’ notion to debate an individual speaker’s cognitive organization of grammar. Spoken and written language settings offer unique stimuli for forming grammar, whilst extra grammar sets for particular genres may be aqcuired also. Speakers may perform routine linguistic activities in casual conversation by using reusable formulaic expressions of different types, but when they conduct more intricate verbal tasks, they may use more abstract grammatical resources covering those that were learned from written language. These suggestions are examined via text and statistical analyses of various Japanese discourse samples.