Infinitive ending

In Persian, infinitives end in “-tan” or “-dan”. Originally, all infinitives ended in “-tan” but it has evolved into “-dan” after vowels and the consonants “n” and “r”.

Original infinitive ending

InfinitiveMeaning
داشتن
dâštan
to have
بستن
bastan
to close
رفتن
raftan
to go
گفتن
goftan
to say

Infinitive ending after vowels

InfinitiveMeaning
آمدن
âmadan
to come
دادن
dan
to give
دیدن
didan
to see
شدن
šodan
to become
بودن
budan
to be

Infinitive ending after “n” and “r”

InfinitiveMeaning
خواند
xwândan
to read; to sing
کندن
kandan
to dig
بردن
bordan
to take; to win
خوردن
xordan
to eat

Apocopated infinitive

Infinitives have a short form, which is technically called “apocopated infinitive”. It is constructed by removing “-an” from the full form. The apocopated form is used in place of the full form in certain cases including the construction of perfective future tense:

Apocopated infinitiveFull infinitive
خواهم رفت
xwâham raft
I will go
خواهم رفتن
xwâham raftan
خواهی رفت
xwâhi raft
You will go
خواهی رفتن
xwâhi raftan
خواهد رفت
xwâhad raft
He/She/It will go
خواهد رفتن
xwâhad raftan

Negative infinitives

The negative form of an infinitive is constructed by prefixing the negation particle na-. When the infinitive begins with a vowel other than “i”, the epenthetic consonant “-y-” appears after “na-” to resolve vowel hiatus. In the case of vowel “i”, the epenthetic consonant is glottal stop.

AffirmativeNegative
بودن
budan
to be
نبودن
nabudan
not to be
رفتن
raftan
to go
نرفتن
naraftan
not to go
آمدن
âmadan
to come
نیامدن
nayâmadan
not to come
ایستادن
istâdan
to stand
نایستادن
naistâdan
not to stand

Passive infinitives

The passive voice is constructed by combining past active participle with a passive-making auxiliary verb, which is typically شدن (šodan). Having a passive infinitive form is typical of transitive verbs.

Active infinitivePassive infinitive
خواندن
xwândan
to read
خوانده شدن
xwânde šodan
to be read
خوردن
xordan
to eat
خورده شدن
xorde šodan
to be eaten

Regarding compound verbs made with کردن (kardan), their passive infinitive is constructed by replacing کردن (kardan) with شدن (šodan).

InfinitivePassive infinitive
باز کردن
bâz kardan
to open
باز شدن
bâz šodan
to be opened, to become open
پاک کردن
pâk kardan
to clean
پاک شدن
pâk šodan
to be cleaned, to become clean

Infinitive as a noun

In Persian, infinitives can act as a noun and accept various prefixes and suffixes. For example, when an infinitive accepts suffix -i, it transforms into an adjective which means "worthy of", "-able", …

InfinitiveDerivation
دیدن
didan
to see
دیدنی
didani
worth seeing
دوست داشتن
dust dâštan
to love
دوست‌داشتنی
dustdâštani
loveable
باور کردن
bâvar kardan
to believe
باورکردنی
bâvarkardani
believable
باور نکردن
bâvar nakardan
not to believe
باورنکردنی
bâvarnakardani
unbelievable

Infinitives as a gerund

In Persian, infinitives can function as what it is known in English as “gerund” or “-ing form”.

شنا کردن برای کمردرد خوب است
Šenâ kardan barâ-ye kamardard xub ast
Swimming is good for back pain