Learn Hardcore Portuguese (Brazil): Este sofá é mais confortável do que a cadeira. - This sofa is more comfortable than the chair.

este / esta / estes / estas – “this / these”, near the speaker
esse / essa / esses / essas – “that / those”, near the listener or something just mentioned
aquele / aquela / aqueles / aquelas – “that / those (over there)”, far from both speaker and listener

In everyday Brazilian Portuguese, people often use esse for many “this/that” situations, but using este for something you’re physically touching or very close to is always correct and sounds natural:

Este sofá – this sofa (right here, next to me)
Esse sofá – that sofa (often near you or already mentioned)
Aquele sofá – that sofa over there (far from both of us)

Why is it este sofá and not esta sofá? Isn’t the word ending in -a usually feminine?

Yes, many nouns ending in -a are feminine, but sofá is an exception: it is masculine.

o sofá – the sofa (masculine)
este sofá – this sofa (masculine demonstrative)

In Portuguese you must learn the gender of each noun with its article:

o sofá (m.)
a cadeira (f.)
o mapa (m.)
a foto (f.) (short for a fotografia)

So the demonstrative has to match the noun’s grammatical gender:

este sofá (masculine)
esta cadeira (feminine)

What exactly does é mean here, and why not está?

é is the 3rd person singular of ser, one of the two verbs “to be”.

ser – used for more permanent or defining characteristics
estar – used for temporary states or conditions

In Este sofá é mais confortável do que a cadeira, the comfort of the sofa is treated as a general, inherent quality of that sofa, so ser (é) is appropriate.

Using está would sound like you’re talking about a temporary condition, e.g. the sofa right now:

Este sofá está mais confortável hoje, depois que trocamos as almofadas.
This sofa is more comfortable today, after we changed the cushions.

How does the comparative structure mais confortável do que work? Is it like adding -er in English?

Yes, this is the standard way to make comparatives in Portuguese. Portuguese does not add -er to adjectives; it uses mais + adjective:

confortável – comfortable
mais confortável – more comfortable
menos confortável – less comfortable

So:

Este sofá é mais confortável do que a cadeira.
This sofa is more comfortable than the chair.

A few adjectives have irregular forms (like English good → better):

bom → melhor (good → better)
ruim / mau → pior (bad → worse)
grande → maior (big → bigger/greater)
pequeno → menor (small → smaller)

But confortável is regular, so you use mais confortável.

Why is it mais confortável do que and not just mais confortável que? Are both correct?

Both are correct and very common in Brazilian Portuguese:

Este sofá é mais confortável do que a cadeira.
Este sofá é mais confortável que a cadeira.

In practice:

do que often sounds a bit more formal or careful.
que alone is very common in everyday speech.

You’ll hear both all the time. For your level, you can treat them as interchangeable in sentences like this.

What is that do in do que? Is it a separate word?

do is a contraction of the preposition de + the masculine article o:

de + o = do
de + a = da
de + os = dos
de + as = das

So do que literally comes from de + o que, which historically you can think of as something like “more comfortable of that which the chair is”, although we never translate it that way.

In modern usage you don’t need to worry about the deeper grammar; just remember:

Comparisons can use … mais/menos + adjective + do que …
Or … mais/menos + adjective + que …

Why doesn’t confortável change its ending to match sofá (masculine) or cadeira (feminine)?

Adjectives in Portuguese fall into two big groups:

Two-form adjectives – different masculine and feminine forms
- bonito / bonita (pretty, handsome)
- branco / branca (white)
Invariable for gender (one form) – same form for masculine and feminine
- interessante – interesting (m/f)
- feliz – happy (m/f)
- confortável – comfortable (m/f)

Confortável belongs to the second group, so it’s:

o sofá confortável – the comfortable sofa (m.)
a cadeira confortável – the comfortable chair (f.)

It does change for number:

singular: confortável
plural: confortáveis

Example in plural:

Estes sofás são mais confortáveis do que as cadeiras.
These sofas are more comfortable than the chairs.

Why do we say a cadeira with the article? Could we just say do que cadeira?

In this sentence, we’re talking about a specific chair (for example, that chair in the room). In Portuguese, specific countable nouns almost always take the definite article:

a cadeira – the chair
o sofá – the sofa

So do que a cadeira is the natural form.

Este sofá é mais confortável do que cadeira sounds wrong in standard Portuguese.

You can drop articles in more generic, “in general” statements:

Sofá é mais confortável que cadeira.
A sofa is more comfortable than a chair / Sofas are more comfortable than chairs (in general).

But once you use este (“this”) and mean one particular chair, you should normally keep the article: a cadeira.

How would I say this sentence in the plural: “These sofas are more comfortable than the chairs”?

You need to make the demonstrative, nouns, verb, and adjective plural:

Este sofá é mais confortável do que a cadeira.
→ Estes sofás são mais confortáveis do que as cadeiras.

Changes:

Este → Estes (this → these, masculine plural)
sofá → sofás
é → são (is → are)
confortável → confortáveis
a cadeira → as cadeiras

How would I say “The sofa is as comfortable as the chair” instead of “more comfortable than”?

For equality comparisons, use tão … quanto or tão … como:

O sofá é tão confortável quanto a cadeira.
O sofá é tão confortável como a cadeira.

Both mean:

The sofa is as comfortable as the chair.

Is the word order fixed? Could I move mais to a different place?

The natural, correct word order is:

Este sofá é mais confortável do que a cadeira.

You cannot move mais around freely. These versions are wrong or extremely unnatural:

✗ Este sofá é confortável mais do que a cadeira.
✗ Este sofá mais é confortável do que a cadeira.
✗ Mais confortável este sofá é do que a cadeira.

Think of mais confortável as a tight unit (“more comfortable”) that must stay together after the verb é:

[Este sofá] [é] [mais confortável] [do que a cadeira].

Why does sofá have an accent mark on the á?

In Portuguese, accent marks often show where the stress (main emphasis) is and sometimes the quality of the vowel.

General rule:
Words ending in a vowel, -n, or -s are normally stressed on the second-to-last syllable.

If sofá followed this rule, it would be stressed as SO-fa.
But the actual pronunciation is so-FÁ, with stress on the last syllable.
The accent á is written to break the default rule and mark the correct stress.

The same thing happens in:

café – ca-FÉ
você – vo-CÊ
também – tam-BÊM

So sofá is pronounced so-FÁ, not SO-fa.

How do you pronounce Este sofá é mais confortável do que a cadeira in Brazilian Portuguese?

Here is a rough, English-friendly pronunciation guide (Brazilian, southern/southeastern style):

Este – “EHSH-chee” (EH + soft SH + chee)
sofá – “so-FAH” (stress on FAH)
é – “eh” (short, open)
mais – “majs” (like English “mice”, but shorter)
confortável – “con-for-TAH-vel”
- con like “kong” but lighter
- for like “for”
- TAH stressed, open “a”
- vel like “vehw” (final l tends to sound like a soft w)
do – “doo” (like “doo”)
que – “keh” (never “kwee”)
a – “ah”
cadeira – “kah-DAY-rah”
- ca like “kah”
- dei like English “day”
- ra like “hah” (Brazilian r varies by region; often like an h here)

Putting it together smoothly (with typical linking):

“EHSH-chee so-FAH eh majs con-for-TAH-vel doo KEH ah kah-DAY-rah.”