Concept:An adjective describes a noun, while other word forms can be nouns, adverbs, or verbs.Explanation:The base word 'Insist' is a verb. Adding the suffix '-ent' forms the adjective 'Insistent'. 'Insistence' is a noun. 'Insistently' is an adverb. 'Insisted' is the past tense verb.Answer:The adjective form is 'Insistent'.