The indefinite suffix is generally used in the following situations:
with the particle هیچ in negative sentences:
"I did not buy any book" هیچ کتابی نخریدم.
"I have told nothing" هیچ چیزی نگفتم.
with a nominal compound predicate that includes an adjective:
"Kabul is a big town" کابل شهر کلانی است.
"She is a beautiful girl" او دختر مقبولی است.
As usual, in this case the suffix is attached to the adjective, which is the last word of the word combination.
The suffix ی (unlike the indefinite article in English) is also used to mark any noun, usually excepting proper nouns, that is modified by a relative clause:
کتابی که من خریدم دلچسپ است.
"The book which I have bought is interesting"
دختری که شما گفتید نیامد.
"The girl you were talking about didn't come."
احمد که دوست من است همسایه شما است.
"Ahmad who is my friend is your neighbor."
The indefinite suffix never carries the stress. Do not expect the application of the terms definite and indefinite in Dari to correspond exactly with their application in English.
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