The Object is a secondary part of the sentence expressed by a verb, a noun, a substantival pronoun, an adjective, a numeral, or an adverb, and denoting a thing to which the action passes on, which is a result of the action, in reference to which an action is committed or a property is manifested, or denoting an action as object of another action.

Objects differ form one another
• by their morphological composition, by the parts of speech or phrases which perform the function of object
• by the type of their relation to the action expressed by the verb (direct/indirect)

Classification of object:
1. Prepositional and non-prepositional objects
2. Morphological types (noun, pronoun, substantivized adjective, infinitive, gerund)
3. Direct/indirect, is applied only to objects expressed by nouns or pronouns. There are sentences in which the predicate is expressed by the verbs send, show, lend, give. These verbs usually take 2 different kinds of objects simultaneously: (1) an object expressing the thing which is sent, shown, lent, given, etc. (2) the person or persons to whom the thing is sent, shown, lent, given, etc. The difference between the 2 relations is clear enough: the direct object denotes the thing immediately affected by the action denoted by the predicate verb, whereas the indirect object expresses the person towards whom the thing is moved, e.g. We sent them a present. The indirect object stands 1st, the direct object comes after it.