این را میخواهم، نه آن یکی.

را is the direct object marker in Persian. It shows which noun is the specific thing being acted on.

So in این را می‌خواهم:

• این = this
• را = marks this as the direct object
• می‌خواهم = I want

A very important point: را usually appears when the object is definite/specific. Since this is a specific item, را is natural here.

In everyday speech, را is often pronounced as ro after a noun or pronoun.

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

So instead of:

• I want this

Persian prefers:

• this + object marker + want-I

That is why you get:

• این را می‌خواهم

The subject I is built into the verb ending, so Persian does not need a separate word for I here.

Because the verb already shows the subject.

In می‌خواهم, the ending -م means I. So می‌خواهم means I want.

You could add من for emphasis:

• من این را می‌خواهم = I want this

But normally, Persian drops the subject pronoun when it is already clear from the verb.

می‌خواهم has several parts:

• می‌- = an imperfective/present marker
• خواه = the verb stem from خواستن = to want
• -م = I

So:

• می‌خواهم = I want

In standard writing, it is usually written with a half-space: می‌خواهم.
You will also often see میخواهم in informal typing, but می‌خواهم is the standard spelling.

In careful/formal pronunciation, it is roughly:

• mi-khâ-ham

The خ sound is like the ch in Scottish loch or German Bach.

In everyday speech, many speakers shorten it, often sounding closer to:

• می‌خوام
• roughly mi-khâm

So learners may see:

• written/formal: می‌خواهم
• spoken/colloquial: می‌خوام

Both relate to the same verb.

آن means that, and یکی literally means one.

So آن یکی means:

• that one
• the other one over there, depending on context

Persian often uses یکی this way when English would say one after this or that.

Compare:

• این یکی = this one
• آن یکی = that one

In your sentence, آن یکی refers to the alternative item.

Because آن by itself usually just means that.
If English would naturally say that one, Persian often says آن یکی.

So:

• نه آن یکی = not that one

If you said only نه آن, it would usually sound incomplete or less natural in this context.

یکی helps make it clear that you are contrasting one item with another.

Here, نه is used to mean no / not, especially in contrast.

In this sentence, it works like:

• ..., not that one

It is a very common way to reject or contrast something.

You could also make the contrast more fully explicit:

• این را می‌خواهم، آن یکی را نه
• این را می‌خواهم، آن یکی را نمی‌خواهم

Those are slightly fuller ways of saying the same basic idea.

Because the second part is an abbreviated contrast.

The full version could be:

• این را می‌خواهم، نه آن یکی را
• or این را می‌خواهم، آن یکی را نمی‌خواهم

But Persian often leaves out words that are easy to understand from context. So نه آن یکی is a natural shortened form.

This kind of omission is very common in Persian conversation.

In everyday spoken Persian, many speakers use اون instead of آن.

So a common colloquial version would be:

• اینو می‌خوام، نه اون یکی

Compare:

• more careful/written: این را می‌خواهم، نه آن یکی
• colloquial speech: اینو می‌خوام، نه اون یکی

So yes, the sentence you were given is natural, but it leans more toward standard written or careful spoken Persian.

Yes. In colloquial Persian, این را often becomes اینو.

So:

• این را می‌خواهم → اینو می‌خوام

This happens because:

• را is often pronounced ro
• after این, it gets merged in fast speech

So learners should be aware of both forms:

• standard: این را
• colloquial: اینو

A very natural spoken version is:

• اینو می‌خوام، نه اون یکی

This corresponds to the more standard form:

• این را می‌خواهم، نه آن یکی

So if you are reading Persian, learn the standard version; if you are listening to everyday speech, expect to hear the colloquial version much more often.

The comma marks a pause and a contrast:

• I want this, not that one

It is similar to English punctuation in contrastive phrases.

In speech, you would usually hear a slight pause before نه آن یکی. The comma is not doing anything mysterious grammatically; it just helps show the contrast clearly.