The Infinitive and Past Stem | Farsi Grammar

Persian dictionaries cite verbs in the infinitive, a form ending in ن -an: رفتن raftan “to go,” خوردن khordan “to eat,” and دیدن didan “to see.” Remove only that final ن, and you get the past stem: رفت، خورد، دید. This operation is regular and is one of the most dependable parts of Persian verb grammar.

The infinitive is a name for the action, not a complete assertion. The past stem, by contrast, is the base used with endings and other material to build many finite and nonfinite forms. English learners gain much more by storing a Persian verb as a two-stem system than by memorizing every tense as an unrelated word.

The basic operation

Dictionary infinitive	Reading	Remove	Past stem	Meaning
رفتن	raftan	ن	رفتraft	go
خوردن	khordan	ن	خوردkhord	eat
دیدن	didan	ن	دیدdid	see
نوشتن	neveshtan	ن	نوشتnevesht	write
آمدن	âmadan	ن	آمدâmad	come
بودن	budan	ن	بودbud	be

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The shortcut is exact: delete the final letter ن, not the whole final syllable. Thus خوردن gives خورد, and رسیدن gives رسید. No further sound change is required to obtain the past stem.

دیشب دیر به خانه رسیدم.

dishab dir be khâne residam.

I arrived home late last night. (neutral standard; رسید + ـم)

مینا نامه را نوشت و همان روز فرستاد.

minâ nâme râ nevesht va hamân ruz ferestâd.

Mina wrote the letter and sent it that same day. (neutral standard; third-person singular has no ending in the simple past)

In رسیدم, the past stem رسید carries the first-person ending ـم. In نوشت, the form consists of the past stem alone because third-person singular simple past has a zero ending. The stem is not itself “past tense” in every environment; it is a building block whose grammatical value comes from the complete construction.

Why it is called the past stem

The simple past attaches personal endings directly to this stem: رفتم، رفتی، رفت، رفتیم، رفتید، رفتند. The same stem also appears after می‌ in the past imperfect, and before ه in the past participle. These patterns let one stored form support an entire family.

Construction	Form from رفت	Function
past stem + personal ending	رفتم	I went
می‌ past stem + ending	می‌رفتم	I was going / used to go
past stem + ه	رفته	gone; past participle base
inflected future auxiliary + bare past stem	خواهم رفت	I will go (formal-neutral)

وقتی زنگ زدی، به محل کار می‌رفتم.

vaqti zang zadi, be mahall-e kâr mi-raftam.

When you called, I was going to work. (neutral standard; می‌ + past stem رفت + ـم)

تا ساعت نه همه آمده بودند.

tâ sâ'at-e noh hame âmade budand.

By nine o'clock, everyone had arrived. (neutral standard; آمده is built from past stem آمد)

The full tense meanings belong on their dedicated pages. At this stage, notice the recurring letters: once رفت and آمد are secure, forms such as می‌رفتم and آمده stop looking arbitrary.

The infinitive is a citation form, not a finite verb

English labels verbs with to: to go, to eat. Persian رفتن and خوردن fill the same dictionary role, but they do not by themselves say who acted or when. A finite sentence needs the appropriate stem, person ending, and any tense or mood marker.

دیروز با هم به بازار رفتیم.

diruz bâ ham be bâzâr raftim.

Yesterday we went to the market together. (neutral standard; finite past)

بعد از شام چای خوردند.

ba'd az shâm chây khordand.

They drank tea after dinner. (neutral standard; خوردن also forms the ordinary expression چای خوردن)

An infinitive can occur as a noun-like expression when the action itself is being discussed or placed after a preposition. That legitimate use is different from treating it as a finite verb.

برای دیدن نمایشگاه به مرکز شهر رفتیم.

barâ-ye didan-e namâyeshgâh be markaz-e shahr raftim.

We went downtown to see the exhibition. (neutral standard; دیدن is noun-like after برای)

This noun-like use is developed on Nominalized Infinitives. It does not cancel the basic rule that دیدن alone cannot mean “I saw” or “they saw.”

Dictionary lookup and the two-stem habit

Most Persian dictionaries list رفتن, not می‌روم or رفتم, as the headword. To look up an unfamiliar past form, remove its personal ending and restore ن: خوردیم contains خورد, pointing to خوردن. This works cleanly once the ending is identified.

Good dictionaries and textbooks often show the unpredictable present stem too, in a notation such as رفتن (رو). Read this as “infinitive رفتن, present stem رو.” The past stem need not be listed separately because it follows automatically by deleting ن. The next page explains why the present stem must be learned rather than calculated the same way.

فعل نوشتن را زیر حرف ن پیدا کردم.

fe'l-e neveshtan râ zir-e harf-e n peydâ kardam.

I found the verb نوشتن under the letter ن. (careful spoken standard; dictionary context)

در فرهنگ لغت، رو به عنوان بن مضارع کنار رفتن آمده است.

dar farhang-e loghat, rav be onvân-e bon-e mozâre' kenâr-e raftan âmade ast.

In the dictionary, رو appears as the present stem beside رفتن. (formal-neutral)

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Record every new verb as infinitive + present stem: for example, نوشتن + نویس. The infinitive already gives you the past stem نوشت; the second entry supplies the information that spelling alone cannot predict.

A short exchange

بن گذشته‌ی شنیدن چیست؟

bon-e gozashte-ye shenidan chist?

What is the past stem of شنیدن? (careful spoken standard)

شنید؛ فقط ن آخر مصدر را بردار.

shenid; faqat n-e âkhar-e masdar râ bardâr.

شنید; just remove the final ن of the infinitive. (informal instruction with standard forms)

Common Mistakes

1. Using the infinitive as a complete past verb

❌ من دیروز به بانک رفتن.

Incorrect — رفتن is the infinitive and has no finite person marking.

✅ من دیروز برای کاری به بانک رفتم.

man diruz barâ-ye kâri be bânk raftam.

I went to the bank on an errand yesterday.

2. Removing more than final ن

❌ ما دیشب در رستوران شام خوریم.

as a simple-past first-plural form

Incorrect in this past-time sentence — خور is the present stem; a simple-past first plural requires past stem خورد plus ـیم.

✅ بن گذشته‌ی خوردن خورد است.

bon-e gozashte-ye khordan khord ast.

The past stem of خوردن is خورد.

3. Writing the imperfective prefix as a separate word

❌ آن زمان هر روز پیاده می رفتم.

Incorrect standard spelling — می‌ attaches with a ZWNJ.

✅ آن زمان هر روز تا مدرسه پیاده می‌رفتم.

ân zamân har ruz tâ madrese piyâde mi-raftam.

At that time I walked to school every day.

4. Attaching an extra person ending to a finished form

❌ ما نامه را نوشتیمند.

Incorrect — a finite verb takes one personal ending, not first-plural ـیم followed by third-plural ـند.

✅ ما پاسخ را همان شب نوشتیم.

mâ pâsokh râ hamân shab neveshtim.

We wrote the reply that same evening.

Key Takeaways

Persian infinitives are dictionary forms ending in ن.
Delete only final ن to obtain the fully predictable past stem.
The past stem supports simple-past, imperfect, participial, and future constructions.
An infinitive can name an action, but it cannot replace a finite verb in an ordinary assertion.
Store the infinitive together with its unpredictable present stem; the infinitive itself supplies the past stem.

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