Retentive

Adjective for Retentive
1. retentive, recollective, long, tenacious (good at remembering) "a retentive mind"; "tenacious memory" 2. retentive (having the capacity to retain something) 3. retentive (having the power, capacity, or quality of retaining water) "soils retentive of moisture"

Adverbs for Retentive
highly; unusually; phenomenally; miraculously; extraordinarily; marvelously; astonishingly; amazingly; unbelievably; incredibly; conveniently; curiously; peculiarly; singularly; particularly; incomparably.