Hi,
Can a person use a noun with an availble standard adjectival form, which he might not realize the existence of it, can use the noun as an adjective and be considered OK?
person tutors vs. personal tutors
institution problems vs. institutional problems
education materials vs. educational materials
reflection tasks vs. reflective tasks
When is the use of available adjectives necessary or a must? What if a person doesn't know the existence of an available adjective? I do admit that those sets of examples seem to give somewhat different impressions in respect to their counter parts but I think, to a person without a keen knowledge of their semantic meanings, the overall impression of phrases might not be all that apparent.