Direct objects are object can be easily be determined by asking whom or what after the verb.
Jeffery drew the lamp. (Jeffery drew what?) Lamp is the direct object.
Indirect object is also in the objective case. Same sentences contain two objects - the direct object and another object which tells to whom or for whom the action is done.
Mother assigned Jeffery the task of calling his dad. (Task is the direct object.) Mother assigned what? (the task) Jeffery is the indirect object. To whom did mother assigned the task? (To Jeffery.)
Transitive Verb has a direct object.
Subject Verb Indirect Object Direct Object
Joan rewarded the boy with a medal.
Intransitive Verb doesn't have a direct object.
Joan rewarded generously.