Eu rabisco no bloco enquanto espero na receção.

Yes. In Portuguese, subject pronouns are often omitted because the verb ending already shows who the subject is.

So:

• Eu rabisco no bloco enquanto espero na receção.
• Rabisco no bloco enquanto espero na receção.

Both are natural.

Including eu can add a little emphasis, contrast, or clarity. In many everyday situations, leaving it out would sound more typical.

Here, rabisco is the verb rabiscar in the 1st person singular present: I doodle / I scribble.

It suggests writing or drawing casually, absent-mindedly, or roughly, rather than writing something carefully.

So it has a slightly more informal feel than a neutral verb like escrevo (I write).

In this sentence, it is a verb: I doodle / I scribble.

But rabisco can also be a noun in other contexts, meaning a scribble or a doodle.

For example:

• Isto é um rabisco. = This is a scribble.

So the word can be either a noun or a verb, depending on the sentence.

Because no is the contraction of:

• em
  • o = no

So:

• no bloco = in/on the pad / notepad

Portuguese very commonly contracts em with the definite article:

• em + o = no
• em + a = na
• em + os = nos
• em + as = nas

So em o bloco would sound wrong in standard Portuguese.

Here, bloco most likely means a notepad, writing pad, or memo pad.

It does not usually suggest a full bound notebook in the same way caderno often does.

So:

• bloco = pad / notepad
• caderno = notebook / exercise book

In this sentence, bloco fits well with the idea of casually scribbling while waiting.

Because Portuguese often uses the present tense for actions happening right now, especially in general descriptions of what someone is doing.

So enquanto espero literally means while I wait, but in natural English it may also correspond to while I’m waiting.

Portuguese does have a progressive form:

• estou a esperar

But in this sentence, the simple present espero is completely natural and idiomatic.

Because once the subject is understood, Portuguese usually does not repeat it unless there is a reason to emphasise it.

So:

• Eu rabisco no bloco enquanto espero na receção.

already makes it clear that the person who scribbles is also the one who waits.

You could say enquanto eu espero, but it is usually unnecessary here.

Enquanto means while.

It links two actions that happen at the same time:

• rabisco no bloco = I scribble on the pad
• enquanto espero na receção = while I wait in the reception area

So it shows simultaneity: one action is happening during the other.

Because na is the contraction of:

• em
  • a = na

So:

• na receção = in/at the reception

Here receção means the reception area, front desk area, or reception in a building such as a clinic, office, or hotel.

Portuguese often uses em where English might use either in or at, so na receção can correspond to in the reception area or at reception.

In this sentence, it most naturally means the reception area or front desk/reception space in a building.

The word receção can also mean reception in other senses, depending on context, but here the meaning is clearly the place where someone waits or checks in.

So espero na receção means something like:

• I wait at reception
• I wait in the reception area

Yes, this spelling is associated with Portugal.

In Brazilian Portuguese, you will usually see:

• recepção

In European Portuguese, after spelling reforms and according to standard usage in Portugal, the common spelling is:

• receção

So this sentence is clearly in Portuguese from Portugal.

Yes. Portuguese allows some flexibility.

For example, these are also natural:

• Enquanto espero na receção, rabisco no bloco.
• Na receção, rabisco no bloco enquanto espero.

The original sentence is very natural and straightforward, but changing the order can shift the emphasis slightly.

For example:

• starting with Enquanto espero... emphasises the time relationship
• starting with Na receção... emphasises the location

Usually, no bloco is the natural choice here.

Even though in English we often say on the pad, Portuguese commonly uses em with this kind of idea, giving:

• no bloco

Using sobre o bloco would sound much less natural in this context. It would suggest a more literal physical position on top of the pad rather than the normal idea of writing in/on it.