A casca e a lata vazia vão para o caixote da reciclagem.

Because the subject is made of two things: a casca + a lata vazia.

In Portuguese, a compound subject normally takes a plural verb:

• A lata vazia vai para o caixote.
• A casca e a lata vazia vão para o caixote.

So vão is the 3rd person plural form of ir here.

Because vazia only describes a lata, not a casca.

So the structure is:

• a casca
• e a lata vazia

The adjective agrees only with lata, which is feminine singular, so you get vazia.

If the adjective described both nouns, it would normally be plural:

• A casca e a lata vazias...

But in this sentence, only the can is being called empty.

Portuguese uses definite articles more often than English.

So where English might sometimes sound fine without the, Portuguese often prefers it:

• a casca
• a lata
• o caixote

This is very normal and natural. English speakers often underuse articles when learning Portuguese.

In Portuguese, when you join two singular nouns with e, each noun usually keeps its own article if both are definite:

• a casca e a lata

That sounds more complete and natural than leaving the second article out.

Repeating the article helps show clearly that these are two separate items.

Because in Portuguese, adjectives usually come after the noun:

• lata vazia
• casa grande
• carro novo

Putting the adjective before the noun is possible in some cases, but it often sounds more literary, emphatic, or changes the nuance. For a straightforward everyday sentence, lata vazia is the normal order.

Casca is a broad word. Depending on the context, it can mean:

• peel
• skin
• shell
• rind

So it is not limited to just one kind of outer layer. Context tells you which English word fits best.

Yes, caixote is very natural in European Portuguese.

It usually means a large box, bin, or container, depending on context. In this sentence, o caixote da reciclagem means the recycling bin/container.

In European Portuguese, words like caixote do lixo and caixote da reciclagem are common. In Brazilian Portuguese, you are more likely to hear lixeira for bin.

Because da is a contraction of de + a.

• de = of
• a = the
• da = of the

So o caixote da reciclagem literally means the bin of the recycling, which English naturally translates as the recycling bin.

This kind of structure is very common in Portuguese.

Para o means to the or into the, depending on context.

Here it shows destination:

• vão para o caixote da reciclagem

In natural English, that becomes something like go in the recycling bin.

Also, in everyday speech, para o is often reduced to pro, especially informally:

• vão pro caixote

But in standard writing, para o is the safe form to use.

Yes. Literally, vão para means go to.

But in Portuguese, especially when talking about sorting waste, this is a very natural way to say that something belongs in a certain bin or should be put there.

For example:

• Isto vai para o lixo.
• Isto vai para a reciclagem.

So even though objects do not literally walk anywhere, Portuguese often uses ir like this in practical instructions.

The difficult part is -ão, which is a very common Portuguese ending.

It is nasal, so it does not sound exactly like any normal English ending. A rough guide is something a bit like vow, but with a nasal sound and without a fully pronounced final consonant.

So:

• vai = singular
• vão = plural

This is a good pair to practise because learners often mix them up. The spelling difference is small, but the pronunciation and grammar are both different.