من قرار را فراموش نکردم.

Yes. من means I, but Persian often drops subject pronouns when the verb already shows the person.

Here, کردم already tells you the subject is I, so:

• من قرار را فراموش نکردم.
• قرار را فراموش نکردم.

both can mean the same thing.

Including من can add emphasis, contrast, or clarity, for example:

• من قرار را فراموش نکردم، او فراموش کرد.
  I didn’t forget the appointment; he/she did.

را marks the direct object, especially when it is specific or definite.

In this sentence:

• قرار = the appointment / arrangement / agreement
• قرار را = the specific appointment/agreement being talked about

So را tells you that قرار is the thing being forgotten.

A very rough comparison in English would be the difference between:

• I forgot an appointment
• I forgot the appointment

Persian uses را to help show that kind of specificity.

Persian usually prefers Subject – Object – Verb order, while English usually uses Subject – Verb – Object.

So:

• English: I did not forget the appointment
• Persian: I the appointment did not forget

That is why the verb comes at the end:

• من = I
• قرار را = the appointment
• فراموش نکردم = did not forget

This verb-final pattern is very common in Persian.

Because فراموش کردن is a very common Persian compound verb meaning to forget.

It is made of:

• فراموش = forgetting / forgotten
• کردن = to do

Together, فراموش کردن means to forget.

In the past negative, it becomes:

• نکردم = I did not do

So:

• فراموش کردم = I forgot
• فراموش نکردم = I did not forget

The negative marker goes on کردم, because that is the conjugated verbal part.

نکردم can be broken down like this:

• نـ = negative prefix
• کرد = past stem of کردن (to do)
• ـم = I ending

So:

• کردم = I did
• نکردم = I did not do

Inside the compound verb فراموش کردن, this gives:

• فراموش کردم = I forgot
• فراموش نکردم = I didn’t forget

قرار can have a few related meanings depending on context, such as:

• appointment
• arrangement
• agreement
• plan

So the exact English translation depends on the situation.

For example:

• meeting someone at a certain time → appointment / date
• an agreed plan → arrangement
• an agreement between people → agreement

This is normal in Persian: one noun can cover several ideas that English splits into different words.

Yes, it is grammatical and understandable.

However, how natural it sounds depends on what قرار means in context.

If قرار means appointment or plan, this sentence can work fine. But in everyday speech, Persian speakers might sometimes choose a more specific noun if the context is clearer, such as:

• قرار ملاقات را فراموش نکردم.
  I didn’t forget the appointment/meeting.

Or they may simply say this sentence if everyone already knows which قرار is being discussed.

So the sentence is correct, but context matters for how natural or complete it feels.

Persian does not have a word exactly like English the.

Instead, definiteness is often understood from context, and را often helps show that the object is specific.

So قرار را often corresponds to the appointment or that appointment, even though there is no separate word for the.

This is a very common adjustment for English speakers learning Persian: Persian usually does not mark definiteness the same way English does.

Yes, depending on context, Persian simple past negatives can sometimes overlap with English expressions like:

• I didn’t forget
• I haven’t forgotten

But the most direct grammatical match here is I didn’t forget.

If a speaker especially wants to emphasize a present result, context usually does the work, though other phrasing is also possible.

So in real usage, Persian and English tense choices do not always line up one-for-one.

A very normal everyday version would be:

• قرار را فراموش نکردم.

This is often the most natural way to say it unless you want to stress I.

In speech, the pronoun is frequently omitted because the verb ending already makes the subject clear.