من او را در خیابان نشناختم.

In Persian, the ending -م in نشناختم already means I, so من is not strictly necessary.

• نشناختم = I did not recognize
• من نشناختم = also I did not recognize

Including من can add clarity, emphasis, or simply sound natural in context. So both of these are possible:

• من او را در خیابان نشناختم
• او را در خیابان نشناختم

The full version with من is a little more explicit.

او is a third-person singular pronoun and can mean:

• he
• she
• sometimes it, depending on context

Persian does not mark grammatical gender in pronouns the way English does, so او does not tell you whether the person is male or female. You understand that from context.

In everyday spoken Persian, او is often replaced by اون or reduced further in connected speech.

را is the direct object marker in Persian. It usually marks a specific or definite direct object.

So in this sentence:

• او را = him/her as the direct object

That is why you cannot usually translate it word-for-word as a separate English word. It is more of a grammatical marker.

Compare:

• او را نشناختم = I didn’t recognize him/her
• without را, the sentence would sound incomplete or unnatural if you mean a specific person

For learners, a helpful shortcut is:

• if the object is a particular person or thing, Persian often uses را

در means in or at, and خیابان means street.

So:

• در خیابان = in the street / on the street

English usually says on the street, but Persian commonly uses در خیابان. So this is a normal place expression, even if the preposition does not match English exactly.

نشناختم comes from the verb شناختن (to recognize / to know in the sense of identifying someone).

It breaks down like this:

• شناخت = past stem
• نـ = negative prefix
• -م = I

So:

• شناختم = I recognized
• نشناختم = I did not recognize

This is the simple past negative form.

In Persian, شناختن often means to know / recognize / be familiar with someone or something, especially in the sense of recognizing a person.

In this sentence, the idea is not just I didn’t know him/her in a general sense. It is more like:

• I didn’t recognize him/her

That is why نشناختم is the natural choice.

A native English speaker may expect a different verb because English separates know and recognize more clearly, while Persian شناختن covers recognition very naturally.

Both are possible forms, but they do not mean exactly the same thing.

• نشناختم = I did not recognize
• نمی‌شناختم = I did not know / I was not recognizing / I wasn’t familiar with

In this sentence, the idea is a completed event at a specific moment: seeing someone in the street and failing to recognize them. For that, نشناختم is the best choice.

So:

• او را در خیابان نشناختم = at that moment, I failed to recognize him/her
• او را نمی‌شناختم = I didn’t know him/her / I was not acquainted with him/her

The basic Persian word order is Subject – Object – Verb, and this sentence follows that pattern:

• من = subject
• او را = object
• در خیابان = place expression
• نشناختم = verb

So the sentence is:

• من او را در خیابان نشناختم

But Persian word order is somewhat flexible, especially for emphasis. For example:

• من در خیابان او را نشناختم
• او را در خیابان نشناختم

These are still natural. The verb usually stays at the end.

In colloquial Persian, this sentence is often said more like:

• من اونو تو خیابون نشناختم

Changes:

• او را → اونو
• در → تو
• خیابان → خیابون

So the spoken version is less formal and much more common in conversation.

Written/formal:

• من او را در خیابان نشناختم

Spoken:

• من اونو تو خیابون نشناختم

A careful pronunciation would be approximately:

• man oo râ dar khiyâbân nashenâkhtam

A more natural spoken pronunciation might sound closer to:

• manoono to xiyâbun nashenâkhtam
• or more carefully: man uno tu xiyâbun nashenâkhtam

A few notes:

• او is pronounced like oo
• را is often pronounced râ, but in speech it may reduce depending on context
• خیابان is commonly pronounced xiyâbân or in speech xiyâbun
• نشناختم begins with na-, the negative prefix

Yes. Persian often drops subject pronouns when the verb ending already makes the subject clear.

So this is perfectly natural:

• او را در خیابان نشناختم

It still clearly means I didn’t recognize him/her in the street, because -م on نشناختم shows the subject is I.

Persian uses explicit subject pronouns less often than English does.

Usually yes. را follows the noun or pronoun that it marks.

So:

• او را is correct
• not را او

With pronouns, the object marker is very tightly connected to the pronoun. In colloquial Persian, they often merge into one spoken unit:

• او را → اونو
• من را → منو
• تو را → تورو

So it is best to think of را as something that directly follows the object it marks.