Basics
Language
 nunit of language components of sentences types of sentence

Words
 word classification part of speech classification
 noun verb adjective adjective2 adverb conjunctives continuation exclamation word auxiliary verb postposition
 postposition postposition postposition postposition
 demonstrative compound word derivative
 conjugation of verbs conjugation of adjective conjugation of adjective2

Forms
 forms of verb forms of adjective spoken language

Honorific
 classification of honorifics polite language beautified language respectful words humility humility2 greetings

Other
 ancient Japanese