Entriamo nella casa degli specchi.

It can mean either, depending on context.

• entriamo is the 1st person plural form of entrare in the present tense.
• So grammatically it means we enter / we are entering.
• But in everyday Italian, the same form is also commonly used as an exhortation: let's enter / let's go in.

So without more context, entriamo can be understood in both ways.

Because Italian usually does not need subject pronouns when the verb ending already shows the subject.

• entro = I enter
• entri = you enter
• entra = he/she enters
• entriamo = we enter

Since -iamo already tells you it is we, the pronoun noi is normally omitted unless you want emphasis.

So:

• Entriamo nella casa degli specchi. = normal
• Noi entriamo nella casa degli specchi. = more emphatic, like we are the ones entering

Because in + la normally contracts into nella.

This is called an articulated preposition.

• in + il = nel
• in + lo = nello
• in + la = nella
• in + i = nei
• in + gli = negli
• in + le = nelle

So:

• nella casa = in the house

Italian usually prefers the contracted form, not in la.

Because casa is a feminine singular noun.

So it takes the feminine singular definite article la:

• la casa = the house

This also affects the preposition:

• in + la casa → nella casa

Because specchi is a masculine plural noun beginning with s + consonant (sp), and that pattern uses gli, not i.

The article system works like this:

• il libro → i libri
• lo specchio → gli specchi

Then with di:

• di + i = dei
• di + gli = degli

So:

• degli specchi = of the mirrors

You get degli because the singular would be lo specchio, not il specchio.

The singular is specchio.

• singular: lo specchio
• plural: gli specchi

The spelling changes to keep the hard k sound.

• specchio is pronounced roughly SPEK-kyo
• In the plural, Italian writes specchi so that the c still sounds hard before i

This is the same idea as:

• amico → amici
• but
• fuoco → fuochi

In specchi, the h helps preserve the hard sound.

degli is the contraction of di + gli.

• di = of
• gli = the (masculine plural form used before certain sounds)

So:

• degli specchi = of the mirrors

In the full phrase:

• la casa degli specchi

Italian often uses this structure where English might use of or a noun modifier.

Because Italian uses definite articles more often than English does.

Here the structure is literally:

• the house of the mirrors

Even if English may prefer a more natural phrase like the house of mirrors or the hall of mirrors, Italian commonly keeps the article with the second noun:

• la casa degli specchi

That is a very normal Italian structure.

Not with the same meaning.

• entrare in casa is an established expression meaning to go home / to go into the house
• But nella casa degli specchi specifically means into the house/hall of mirrors

So in this sentence, nella is the natural choice because you are entering a specific place: the house of mirrors.

Yes, but Italian often starts directly with the verb, especially in narration or when the subject is obvious.

So:

• Entriamo nella casa degli specchi. = natural
• Noi entriamo nella casa degli specchi. = possible, but more emphatic

Starting with the verb can sound more immediate, like the action is happening right now.

A simple pronunciation guide is:

en-TRYAH-mo NEL-la LAH-zah DEHL-lyee SPEK-kee

A few details:

• entriamo: stress on -a- → en-TRIA-mo
• nella: NEL-la
• casa: in standard Italian, usually KAH-sa
• degli: this can be tricky; it sounds roughly like DEHL-lyee
• specchi: SPEK-kee

The hardest parts for many English speakers are usually gli and specchi.