A camisa e a saia estão na cadeira; eu vou guardar as duas no armário.

In Portuguese, definite articles are used much more often than in English. So a camisa and a saia literally mean the shirt and the skirt, and this sounds natural in Portuguese even when English might simply say shirt and skirt in some contexts.

Here, the speaker is referring to specific items, so the articles are expected:

• a camisa = the shirt
• a saia = the skirt

Because the subject is plural: a camisa e a saia.

Even though each noun is singular by itself, together they form a plural subject:

• a camisa = the shirt
• a saia = the skirt
• a camisa e a saia = the shirt and the skirt

So the verb estar must also be plural:

• está = is
• estão = are

That is why:

• A camisa e a saia estão na cadeira. = The shirt and the skirt are on the chair.

Na is a contraction of:

• em = in / on / at
• a = the

So:

• em + a = na

In this sentence:

• na cadeira = on the chair / literally in the chair depending on context, but here naturally on the chair

Portuguese normally contracts em with definite articles:

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

For the same reason as na cadeira. No is the contraction of:

• em
  • o = no

So:

• no armário = in the closet / wardrobe

The noun armário is masculine, so it takes o:

• o armário
• em o armário becomes no armário

You usually learn the gender together with the noun:

• a cadeira = the chair
• o armário = the closet / wardrobe

Some endings give clues:

• nouns ending in -a are often feminine, like cadeira
• nouns ending in -o are often masculine, but armário ends in -o and is masculine

Still, gender is something you often need to memorize with each noun. A good habit is to learn nouns with their article:

• not just cadeira, but a cadeira
• not just armário, but o armário

Eu vou guardar is a very common way in Brazilian Portuguese to talk about the near future. It literally means I am going to put away/store.

This structure is:

• ir in the present tense + infinitive

So:

• eu vou guardar = I’m going to put away

Other possibilities exist:

• guardarei = I will put away
• guardo can sometimes refer to present or near-future meaning depending on context, but here it would not be the most natural choice

In everyday Brazilian Portuguese, vou + infinitive is extremely common and natural.

Guardar has a broad meaning: to keep, to store, to put away, to save, depending on context.

In this sentence, because clothes are being moved into the closet/wardrobe, the most natural meaning is:

• to put away
• or to store

So:

• eu vou guardar as duas no armário = I’m going to put both of them away in the closet

Because the speaker is referring to two feminine nouns:

• a camisa
• a saia

So the phrase must be feminine plural:

• as duas = the two / both of them

Compare:

• os dois = masculine plural
• as duas = feminine plural

Since both items are feminine, Portuguese uses the feminine form.

It can mean either, depending on how you translate it into natural English.

Here, as duas refers back to the two previously mentioned items, so in English you would often say:

• both of them
• or the two of them

So:

• eu vou guardar as duas no armário = I’m going to put both of them in the closet

In Portuguese, it is normal to use the article with each noun:

• a camisa e a saia

Leaving out the second article is much less natural here. Portuguese tends to be more explicit with articles than English in this kind of coordination.

So the most natural version is:

• a camisa e a saia

Not strictly. Portuguese often drops subject pronouns when the verb already makes the subject clear.

So both are possible:

• eu vou guardar as duas no armário
• vou guardar as duas no armário

Both are natural. Adding eu may give a little more emphasis or clarity, but it is not required.

Portuguese has two verbs for to be: ser and estar.

Here, estar is used because the sentence talks about location:

• A camisa e a saia estão na cadeira. = The shirt and the skirt are on the chair.

A very useful rule:

• ser = identity, permanent characteristics, classification
• estar = location, condition, temporary states

For location of things, estar is the normal choice.

The semicolon links two closely related ideas:

• A camisa e a saia estão na cadeira
• eu vou guardar as duas no armário

It is similar to a stronger comma or a softer period. It shows that the second idea follows naturally from the first.

You could also write:

• A camisa e a saia estão na cadeira. Eu vou guardar as duas no armário.

That would also be correct.

Yes. Since a camisa and a saia are feminine plural, you could replace them with the direct object pronoun as:

• Vou guardá-las no armário. = I’m going to put them away in the closet.

That is grammatically correct. However, in everyday Brazilian Portuguese, many speakers prefer clearer, less clitic-heavy phrasing such as:

• vou guardar as duas no armário
• vou guardar elas no armário is common in speech, though more informal and often avoided in formal grammar teaching

So as duas is a very natural and clear choice here.