The grammatical category tense denotes the temporal relation between a so-called temporal reference point (normally the act of speech) and the act expressed by the verb phrase.

The three m‌ain subcategories of tense are:

1. Past: The act expressed by the verb phrase happens before the temporal reference point:

   من نهار خوردم.

   من هر روز نهار می‌خوردم.

   من داشتم نهار می‌خوردم.

2. Present: The statement of the verb phrase is valid at the temporal reference point:

   من هر روز نهار می‌خورم.

   من دارم نهار می‌خورم.

   As mentioned, the temporal reference point normally equates to the act of speech. However, it can also be displaced into the past, in this occurence, the verb phrase appears in the present tense, while its action happens in the past:

   • When reciting a story:

     منصور دست‌ش را در جیب‌ش می‌کند، ولی چاقوی‌ش را نمی‌یابد. همان موقع گلوله‌ای از پشت صفیر می‌کشد و …

   • When reporting a statement:

     رازی عقیده‌یِ خود را چنین ابراز می‌دارد که …

     غزالی در همین باره می‌گوید …

3. Future: The act of the verb phrase happens after the temporal reference point:

   من فردا نهار خواهم خورد.

   It appears that in Indo-European languages the future tense is originally a subordination with content clause which is felt by most speakers as a consistent verb phrase by the grammaticalization. In Persian, modal verbs with the infinitive /xɒstæn/ خواستن are used for this purpose, as the example above demostrates (see 18•۲•e•b•c.).

   This circumstance suggests that the future tense has been consolidated with the subcategory present in these languages. Therefore, verb phrases can be used for these two cases with the same syntax:

   من فردا نهار می‌خورم.

Besides these subcategories, one can note also others, called “secondary tenses” of those “primary tenses”:

• A group of tense subcategories refer to one of the following cases:
  • For stative verb phrases indicating a certain states, which have existed ever since a moment before the primary tense:

    او خیلی از تهدیدهایِ تو ترسیده بود.

    من همیشه خوبِ تو را خواسته‌ام.

  • For dynamic verb phrases indicating processes, which have ended a moment before the primary tense and have caused a modification, whose effect persists until the primary tense:

    باد پنجره را شکسته.

    من صندلی را رنگ زده‌ام.

  In Persian, like on most of Indo-European languages, verb phrases in these tense subcategories are generated with perfect participles:

  1. Pre-past:

     من پیش از رسیدنِ دیگران نهار خورده بودم.

  2. Pre-present:

     من نهار خورده‌ام.

  3. Pre-future:

     من پیش از رسیدنِ دیگران نهار خورده خواهم بود.

• On the other hand, there are some subcategories which appear only with punctual verb phrases, and indicate that a coming action is foretold at the primary tense. These subcategories are also ordered regarding the primary tenses:
  1. Post-past:

     شاخه‌اش می‌خواست از سنگینی بشکند.

     بهایِ نفت داشت به سطحِ سالِ پیش می‌رسید.

  2. Post-present:

     شاخه‌اش می‌خواهد از سنگینی بشکند.

     بهایِ نفت دارد به سطحِ سالِ پیش می‌رسد.

  3. Post-future:

     به خانه که رسیدی سری به درختِ نسترن بزن! اگر شاخه‌اش می‌خواست از سنگینی بشکند، هَرَس‌ش کن!

     فردا بازارِ بورس را با دقتِ زیرِ نظر داشته باش! اگر بهایِ نفت داشت به سطحِ سالِ پیش می‌رسید، به من خبر بده!

  The examples above demonstrate that these subcategories did not originally exist in Persian, and are first realized by means of compound verb phrases:

  • Subordination with content clause with a modal verb with the infinitive /xɒstæn/ خواستن (see 18•۲•e•b•c.).

    If the verb phrase is in the post-past, the predicate of the content clause can appear in archaic idioms (like in the syntax of verb phrases in the future tense) in the form of infinitus (see 12•۱•d.):

    آن روز که بامداد سلطان به فتحِ خلیج بیرون خواستی شد، ده هزار مرد به مزد گرفتند.

    Nasir Khusraw (11^th Century AD)

  • Subordination with content clause with a modal verb with the infinitive /dɒʃtæn/ داشتن in modern idioms (see 18•۲•e•b•d.).

  In addition (mostly in colloquial speech), verb phrases which are originally and syntactically in the past tense are used in the post-present tense (by means of displacement of the temporal reference point):

  آمدم!

  بگیرش! افتاد!

  ما برفتیم! تو دانیّ و دلِ غم‌خورِ ما!

  بختِ بد تا به کجا می‌برد آبشخورِ ما!

  Hafez (14^th Century AD)