A noun and the words that modify it, form a group together. This group is technically called a noun phrase. In its simplest form, a noun phrase consists of a bare noun i.e. a noun without any adjectives or other modifiers. It is important to know about the concept of noun phrases because in Persian, some grammatical elements are added to the end of a noun phrase rather than to its noun. For example, Persian's indefinite article (-i) is added to the end of a noun phrase.
If a noun phrase consists of only a noun, this means that the indefinite article comes right after the noun:
When a noun phrase consists of a noun and one or modifiers, this means that the indefinite article comes after the last element of the noun phrase:
|a good book|
|کتاب خوب و آموزندهای
ketâb-e khub o âmuzande-i
|a good and informative book|
In English, the indefinite article is added to the beginning of a noun phrase whereas in Persian, it is added to its end.