The indirect object tells to whom or what the action of the verb is directed or for whom or what the action is performed.
Every year, the university gives several outstanding
students full scholarships.
Indirect objects of verbs can instead be made objects of prepositions.
Every year, the university gives full scholarships to several
outstanding students.
Some transitive verbs require the expression of indirect objects in the sentence, whereas other verbs allow the presence of indirect objects but do not require them.