Pur di ricevere una risposta in tempo, mando una raccomandata oggi stesso.

Pur di + infinitive is a fixed expression that means something like in order to, just to, for the sake of, or if only to.

Compared with a plain purpose expression, it often adds a stronger nuance: the speaker is willing to do something, sometimes something inconvenient or extra, to achieve that goal.

So here Pur di ricevere una risposta in tempo suggests: to make sure I get a reply in time, or just to get a reply in time.

It is stronger and more emotionally marked than a simple per ricevere.

Both can introduce purpose, but they are not identical.

• Per ricevere una risposta in tempo, mando una raccomandata = neutral purpose: I’m sending a registered letter to receive a reply in time.
• Pur di ricevere una risposta in tempo, mando una raccomandata = stronger: I’m sending a registered letter, just to make sure I get a reply in time / because I really want a reply in time.

So pur di gives the idea of stronger motivation, determination, or willingness to take extra measures.

Because after pur di, Italian uses the infinitive.

So the pattern is:

pur di + infinitive

Examples:

• pur di capire
• pur di arrivare
• pur di ricevere

You do not use a conjugated verb directly after di in this structure.

By default, the understood subject of ricevere is the same as the subject of the main verb mando.

So the sentence naturally means:

I send a registered letter today so that I can receive a reply in time.

This is a common feature with infinitive clauses in Italian: the subject is often implied and understood from the main clause.

If you wanted a different person to receive the reply, you would usually need to make that explicit, for example with a pronoun or a different construction.

Italian often uses the present tense to talk about something planned for the near future, especially when there is a clear time expression such as oggi stesso.

So mando una raccomandata oggi stesso sounds natural and immediate: I’m sending a registered letter today itself / today without delay.

You could also say manderò, but that would sound a bit more like a simple future statement:

• mando = immediate, decided, almost already set in motion
• manderò = future action, slightly less direct

Una raccomandata is short for una lettera raccomandata.

It means a registered letter: a letter sent through a postal service with official tracking and proof of sending and/or delivery.

In everyday Italian, people very often just say una raccomandata without repeating lettera.

So:

• mandare una raccomandata = to send a registered letter

Here stesso is an intensifier. It does not mean same in the usual sense.

With time expressions, stesso means something like:

• this very
• as early as
• without waiting

So:

• oggi = today
• oggi stesso = today itself / as early as today / today without delay

It adds urgency or emphasis.

You also see this with other time words:

• domani stesso = tomorrow itself
• stasera stessa = this very evening

Because in tempo is the normal expression for in time or on time in this kind of context.

So:

• ricevere una risposta in tempo = to receive a reply in time

By contrast, a tempo usually has other meanings, especially:

• in rhythm / in time in music
• sometimes at a set rate in other contexts

So in this sentence, in tempo is the correct choice.

The comma is natural because Pur di ricevere una risposta in tempo is an introductory clause explaining the motive or purpose of the main action.

So the comma helps separate:

• the purpose/motivation clause from
• the main clause

Without the comma, the sentence would still be understandable: Pur di ricevere una risposta in tempo mando una raccomandata oggi stesso.

But with the comma, it reads more clearly and more naturally.

Una risposta means a reply, in a general, non-specific sense.

The speaker is not referring to one already identified reply, but to the fact of getting some reply.

If you said la risposta, that would usually suggest a specific reply already known or expected:

• una risposta = any reply / a reply
• la risposta = the specific reply

So una risposta is the most natural choice here.