— clarifying
— demonstrative
— didactic
— didactical
— doctrinaire
— educational
— educative
— elucidative
— explanatory
— expositive
— expository
— illustrative
— inactive
— inextricable
— informative
— informatory
— inside
— installation
— instance
— instant
— instate
— instigate
— instigation
— instigator
— instill
— instinctive
— institute
— institution
— instruct
— instructed
— instruction
— instructional
— instructor
— instrument
— interpretative
— interpretive
— ostensive
— preachy