Learn Hardcore Portuguese (Portugal): Nós esperamos em frente ao mercado.

Nós esperamos em frente ao mercado – a bit more emphatic: we wait…
Esperamos em frente ao mercado – more neutral and very natural in everyday speech.

You usually keep Nós only for emphasis or when you really want to highlight the subject or avoid ambiguity.

Can esperamos also mean we hope here, or does it only mean we wait?

The verb esperar has two main meanings:

to wait
to hope / to expect

In this sentence, because it comes with a place expression (em frente ao mercado), it can only mean we wait.

Nós esperamos em frente ao mercado. → We wait / are waiting in front of the market.

If you wanted we hope, you would normally follow it with a clause:

Nós esperamos que ele venha. – We hope that he comes.

So here, the context forces the meaning to wait.

Shouldn’t it be esperamos por to mean we wait for? Where is the for in Portuguese?

In Portuguese, esperar can work both with and without por:

Esperamos por ti. – We wait for you.
Esperamos o autocarro. – We wait for the bus. (no por, direct object)

In your sentence, there is no object (no “someone” or “something” we’re waiting for), only a place:

Nós esperamos em frente ao mercado. – We wait (are waiting) in front of the market.

Because there is no person/thing after the verb, there is nothing for por to attach to, so por is not used here at all.

Is esperamos a present tense meaning we are doing it right now, or a habitual action?

Esperamos is the present indicative and can express both:

A habit:
- Todos os dias, nós esperamos em frente ao mercado.
  Every day, we wait in front of the market.
An action happening right now (if the context makes that clear):
- (On the phone:) Nós esperamos em frente ao mercado.
  We’re waiting in front of the market (right now).

If you want to sound explicitly like English “we are waiting”, especially in European Portuguese, you can use:

Estamos à espera em frente ao mercado.
Estamos a esperar em frente ao mercado. (possible, but estar à espera is more idiomatic in Portugal)

What exactly does em frente mean, and how is it different from à frente or na frente?

Em frente (de / a) usually means physically in front of, facing something:

em frente ao mercado – in front of / opposite the market

Common contrasts:

em frente (de/a) – neutral, standard for physical “in front of”:
- O carro está em frente à casa. – The car is in front of the house.
na frente (de) – very similar, a bit more colloquial, often “right in front of”:
- Estamos na frente do mercado.
à frente de – often “ahead of” (in a queue, a list, a race):
- Ele está à minha frente na fila. – He is ahead of me in the line.

In your sentence, em frente ao mercado is the standard, neutral choice.

Why is it em frente ao mercado and not em frente do mercado? Are both correct?

Both are grammatically correct and used in European Portuguese:

em frente ao mercado – in front of the market
em frente do mercado – in front of the market

Many speakers use them almost interchangeably. Some grammar books suggest a subtle difference:

em frente de – more about position (“in front of it”)
em frente a – can suggest facing towards something

But in everyday speech, em frente ao mercado and em frente do mercado are both very common, and nobody will worry about that nuance in a sentence like this.

What exactly is ao here?

Ao is a contraction of:

a (preposition “to / at / towards”)
o (masculine singular definite article “the”)

So ao mercado literally = a + o mercado → ao mercado.

In this expression, we have:

em frente a
- o mercado → em frente ao mercado

If the noun were feminine, you’d get à (with a grave accent):

a + a loja → à loja
em frente à loja – in front of the shop

Could I say em frente a o mercado instead of em frente ao mercado, without contracting?

In normal Portuguese, no. The contraction is mandatory in standard speech and writing:

a + o → ao
a + os → aos
a + a → à
a + as → às

So you should say:

em frente ao mercado – correct
em frente a o mercado – sounds wrong / foreign to native ears

Only in extremely marked, slow, artificial speech (for emphasis or teaching) might someone pronounce a o separately, but in real usage you always contract it.

Why is it ao mercado and not no mercado or para o mercado?

Different prepositions express different relationships:

em frente a – in front of (a fixed expression)
- em frente ao mercado – in front of the market
em / no – in, at (location inside or simply at):
- no mercado – in/at the market
para / a – to, towards (direction / destination):
- para o mercado – to the market

Here you want the idea in front of, so you must use the fixed structure em frente a + article:

em frente ao mercado, not no mercado and not em frente para o mercado.

Why do we need the article o in ao mercado? Can I say em frente a mercado?

With a specific, countable singular noun like mercado, European Portuguese almost always uses the definite article:

em frente ao mercado – in front of the market (a particular market we both know)

Em frente a mercado is ungrammatical in this sense. Article-less singulars after a are very restricted in Portuguese and don’t work like English “in front of market”.

You could omit the article only in more abstract or plural contexts, e.g.:

em frente a mercados concorrentes – in front of competing markets (here mercados is plural and generic)

Can I move em frente ao mercado to the beginning of the sentence? Is Em frente ao mercado, nós esperamos correct?

Yes, that is correct and natural:

Nós esperamos em frente ao mercado.
Em frente ao mercado, nós esperamos.

Both are fine.

In Portuguese, it’s quite common to move place and time expressions to the beginning for emphasis or style. Just keep the internal order of the phrase the same:

em frente ao mercado (correct)
ao mercado em frente (incorrect)

How would this change if the noun were feminine instead of masculine?

The preposition–article contraction changes with gender:

Masculine singular: a + o → ao
- em frente ao mercado – in front of the market
Feminine singular: a + a → à
- em frente à loja – in front of the shop
Masculine plural: a + os → aos
- em frente aos bancos – in front of the banks
Feminine plural: a + as → às
- em frente às casas – in front of the houses

The rest of the structure (em frente a…) stays the same; only the article changes to match the noun.

How do you pronounce Nós esperamos em frente ao mercado in European Portuguese?

Approximate European Portuguese pronunciation:

Nós – [nɔʃ] (like nosh with a shorter vowel)
esperamos – [ɨʃpɨˈɾɐmuʃ]
- initial e is a very reduced vowel [ɨ], almost like an unstressed “uh”
- stress on -ra-: es-pe-RA-mos
em – [ẽj̃] (nasal, a bit like ay through the nose)
frente – [ˈfɾẽtɨ] (stress on fren-, nasal vowel)
ao – [aw] (like English ow in cow)
mercado – [mɨɾˈkaðu] (stress on -ca-, final -do sounds like -du)

All together, roughly:
[nɔʃ ɨʃpɨˈɾɐmuʃ ẽj̃ ˈfɾẽtɨ aw mɨɾˈkaðu]

Is there any more “continuous” way, in European Portuguese, to say We are waiting in front of the market?

Yes. European Portuguese often uses estar a + infinitive or estar à espera:

Estamos à espera em frente ao mercado.
Estamos a esperar em frente ao mercado.

Both can correspond closely to English “We are waiting in front of the market”, making it clearer that the action is happening right now.
However, in context, simple Nós esperamos em frente ao mercado can also refer to a current, ongoing action.