The object of a verb is the noun, pronoun or other noun substitute that receives the results of the action referred to by the verb. Objects of verbs may be either direct objects or indirect objects. Prepositions also have objects.
Verbs that take direct objects are termed transitive verbs. In general, do not allow any words to separate the verb and its direct object. Indirect objects, however, are often an exception.
The Everglades Coalition promoted tirelessly an effort
to save the area's unique biological capital.
The Everglades Coalition tirelessly promoted an effort
to save the area's unique biological capital.
--Norman Boucher, "Back to the Everglades," Technology Review
You can change a sentence from active voice to passive voice by making the object of the active verb (direct object or indirect object) the subject of the passive verb and adding a form of the passive auxiliary be to the verb phrase.
J. Robert Oppenheimer gave the first comprehensive description
of a neutron star in 1939, shortly before he began working on the first
atomic bomb.
The first comprehensive description of a neutron star
was given by J. Robert Oppenheimer in 1939, shortly before he began working on
the first atomic bomb.
--William J. Kaufmann, "The Black Hole"