Minha mãe prefere usar a secadora no inverno, mas no verão ela usa o varal.

Because the possessive adjective agrees with the thing possessed, not with the speaker.

• mãe is a feminine noun
• so you use minha = my for a feminine singular noun

Examples:

• minha mãe = my mother
• meu pai = my father
• minha casa = my house
• meu carro = my car

Yes, A minha mãe is also possible in Portuguese. In Brazilian Portuguese, both patterns exist:

• Minha mãe prefere...
• A minha mãe prefere...

In Brazil, leaving out the article before a possessive is very common, especially in simple neutral sentences. Adding the article can sound a little more natural in some regions or contexts, but here minha mãe without a is completely normal.

Because preferir is followed directly by the infinitive.

So:

• prefere usar = prefers to use

Not:

• prefere de usar ❌

This is similar to other verbs in Portuguese that are followed directly by an infinitive:

• gosta de usar = likes to use
• quer usar = wants to use
• precisa usar = needs to use

Notice that some verbs need a preposition and some do not:

• preferir usar ✅
• gostar de usar ✅

Portuguese often uses definite articles where English would not.

Here, usar a secadora and usar o varal sound natural because the speaker is referring to those things in a general, familiar, real-world way.

So Portuguese commonly says:

• usar a secadora
• lavar a roupa
• fechar a porta

Even when English might say:

• use the dryer / use a dryer / use dryer
• wash clothes
• close the door

In this sentence, the articles make the sentence sound natural and idiomatic.

Here, secadora means clothes dryer.

Secador usually means dryer in a more general sense, and very often it refers to a hair dryer:

• secador de cabelo = hair dryer

For laundry, secadora is the normal word:

• secadora de roupas = clothes dryer
• often shortened to just secadora

So in this sentence, a secadora is definitely the laundry machine.

Varal usually means a clothesline.

In context, it is the place where clothes are hung to dry naturally. Depending on the situation, it can be:

• an outdoor clothesline
• an indoor line
• sometimes a drying rack-type setup

But the closest basic translation is clothesline.

Because no is a contraction of:

• em
  • o = no

And both inverno and verão are masculine singular nouns:

• o inverno
• o verão

So:

• em o inverno → no inverno
• em o verão → no verão

This is very common in Portuguese.

Other examples:

• na escola = em + a
• nos Estados Unidos = em + os
• nas férias = em + as

Because each time expression needs its own preposition + article combination.

The sentence contrasts two separate situations:

• no inverno
• no verão

You cannot normally skip the second no here. Portuguese keeps both expressions complete.

So this is natural:

• no inverno, mas no verão

Not:

• no inverno, mas verão ❌

Yes, it could.

Portuguese often drops subject pronouns when the verb already makes the subject clear:

• mas no verão usa o varal

That would still be correct.

But ela is included here for clarity and contrast. It helps reinforce that we are still talking about my mother, especially after the comma and the contrast with mas.

So:

• mas no verão ela usa o varal = slightly clearer / more explicit
• mas no verão usa o varal = also natural

Because Portuguese uses the simple present to talk about habitual actions or general preferences.

This sentence does not mean she is using them right now. It means this is her usual pattern:

• in winter, she prefers to use the dryer
• in summer, she uses the clothesline

So the present tense here expresses routine or habit, just like English can do in:

• She uses the dryer in winter.
• She prefers...

Prefere usar a secadora means she prefers to use the dryer. It expresses a preference.

It does not necessarily mean she always uses it, only that it is her preferred option.

By contrast:

• usa a secadora = she uses the dryer

So the sentence is slightly nuanced:

• in winter, it emphasizes preference: prefere usar
• in summer, it states the action more directly: usa o varal

Yes, but but is the most direct translation here.

• mas = but

It is the most common and neutral way to connect contrasting ideas in everyday Portuguese.

Porém, contudo, and entretanto can also express contrast, but they are usually more formal or stylistically marked.

So in this sentence, mas is the most natural choice.

It can be changed somewhat.

The original sentence is perfectly natural:

• Minha mãe prefere usar a secadora no inverno, mas no verão ela usa o varal.

But Portuguese allows other natural orders, for example:

• No inverno, minha mãe prefere usar a secadora, mas no verão ela usa o varal.
• Minha mãe, no inverno, prefere usar a secadora, mas no verão usa o varal.

The meaning stays basically the same, but the emphasis changes slightly. Putting no inverno first highlights the time frame more strongly.

A few helpful pronunciation notes:

• mãe: has a nasal sound; it is roughly like my with a nasal vowel, but not exactly the same as English
• secadora: stress on do → se-ca-DO-ra
• verão: stress on the last syllable → ve-RÃO
• varal: stress on the last syllable → va-RAL

Also:

• ão in verão is a very common nasal ending in Portuguese
• final l in Brazilian Portuguese often sounds somewhat like an English w sound, so varal may sound a bit like va-RAU

A common pattern is:

• preferir X a Y = to prefer X to Y

Examples:

• Ela prefere a secadora ao varal. = She prefers the dryer to the clothesline.
• Eu prefiro café a chá. = I prefer coffee to tea.

In everyday speech, some Brazilians also use structures influenced by spoken usage, but the classic pattern learners should know is:

• preferir X a Y

In your sentence, though, there is no direct X to Y comparison structure. It simply says:

• prefere usar a secadora no inverno
• mas no verão ela usa o varal