Demonstratives
   

The Demonstrative Adjective: When any of the demonstratives این in ‘this’ and آن ān ‘that, it’ accompany a noun, functioning as an adjective would, then it is called a demonstrative adjective. In Persian they are invariably singular, even when they modify a plural noun. Compare and contrast the following Persian and English sentences:

this book in ketāb [tag resources demonstratives_01a]این کتاب[/tag]
that notebook ān daftar [tag resources demonstratives_02a]آن دفتر[/tag]
these books in ketāb hā [tag resources demonstratives_03]این کتاب ها[/tag]
those notebooks ān daftar hā [tag resources demonstratives_04]آن دفترها[/tag]

The Demonstrative Pronoun: When the demonstrative replaces a noun (as a pronoun normally does), it is referred to as the demonstrative pronoun. In this case, they are pluralized when necessary, as any pronoun would:

This is a man. in mard ast [tag resources demonstratives_05].این مرد است[/tag]
That is a woman. ān zan ast [tag resources demonstratives_06].آن زن است[/tag]
These are men. in mard hastand [tag resources demonstratives_07].این ها مرد هستند[/tag]
Those are women. ān hā zan hastand [tag resources demonstratives_08].آن ها زن هستند[/tag]

A generic noun is invariably singular even when it is modified by a plural demonstrative pronoun:

[tag resources demonstratives_09].این زن است [/tag]
in zan ast
“This is (a) woman.”

[tag resources demonstratives_10].این ها زن هستند[/tag]
in hā zan hastand
“These are women.”

[tag resources demonstratives_11].این پسر دانش آموز است[/tag]
in pesar dāneš āmuz ast
“This boy is (a) student.”

[tag resources demonstratives_12].آن پسرها دانش آموز هستند [/tag]
ān pesar hā dāneš āmuz hastand
“Those boys are students.”