عنوان مقاله [English]
On the basis of Andre Martinet's Functional theory , "subject" is not a universal concept. However we can show the function of subject in many languages, since the probable existence of subject and its properties can be studied and investigated. In Italian language, the shortest sentence contains both subject and predicate. Therefore existence of both is necessary for constructing a sentence.
The most important function of subject is actualization of predicate. For this reason, subject should not be omitted. In Italian, position of obligatory subject is fixed and appears in many sentences as verb endings. So it can not be separated from the predicate.
In addition to this subject, another element often appears too. This new element agrees with the obligatory subject in number, person, and sometimes in gender. But its principal specification is to be arbitrary .This arbitrary subject is omitable and has no fix position in a sentence.