A viagem foi incrível.

A is the feminine singular definite article, meaning the.

So:

• a viagem = the trip / the journey

In Portuguese, nouns have grammatical gender, and viagem is feminine, so it takes a in the singular.

Compare:

• a viagem = the trip
• uma viagem = a trip

Yes, viagem is a feminine noun: a viagem.

Unfortunately, noun gender in Portuguese is not always predictable from meaning alone, so you often need to learn it together with the noun. A good habit is to memorize nouns with their article:

• a viagem
• o carro
• a cidade

Even though many feminine nouns end in -a, viagem is a good reminder that feminine nouns can end in other letters too.

Foi is the third-person singular preterite form of ser.

Here it means was:

• A viagem foi incrível. = The trip was incredible.

It is third-person singular because the subject is a viagem, which is singular.

A quick comparison with ser:

• eu fui = I was / I went
• você/ele/ela foi = you/he/she was
• a viagem foi = the trip was

Both can translate to was, but they are used differently.

• foi (preterite) usually presents the trip as a completed whole
• era (imperfect) gives more of a background, descriptive, or ongoing feeling

So:

• A viagem foi incrível. = The trip was incredible.
  This is the most natural way to make a simple statement about a finished trip.

• A viagem era incrível. sounds less natural by itself in most contexts. It might appear in storytelling, especially if you are describing how things seemed during some period.

For a completed event like a trip, foi is usually the expected choice.

Yes, you might hear estava incrível, but foi incrível is the most common and neutral choice here.

The difference is roughly:

• foi incrível = the trip was incredible overall
• estava incrível = the trip was amazing at that moment / in that state

With something like viagem, Portuguese often uses ser to evaluate the event as a whole.

So if you just want to say The trip was incredible, A viagem foi incrível is the safest, most natural sentence.

Because incrível is one of many adjectives that have the same form for masculine and feminine.

So you get:

• o filme incrível
• a viagem incrível

It only changes for number:

• a viagem incrível = the incredible trip
• as viagens incríveis = the incredible trips

This is normal for many adjectives ending in -vel.

A natural Brazilian pronunciation is approximately:

ah vee-AH-zhem foy een-kreh-SEE-vel

A few important points:

• viagem sounds like vee-AH-zhem
  • the g sounds like the s in measure or the zh sound
• foi sounds roughly like foy
• incrível has stress on crí: in-CRÍ-vel

The final m in viagem does not sound like a strong English m. It mainly nasalizes the vowel before it.

This sentence uses the normal, neutral order:

• A viagem = subject
• foi = verb
• incrível = predicate adjective

So A viagem foi incrível is the standard way to say it.

You can change word order in special cases for style or emphasis, but it is much less common for learners and may sound literary or marked. The basic pattern you should remember is:

subject + verb + adjective

Normally, no. In this sentence, a is needed.

• A viagem foi incrível. = The trip was incredible.

Without the article, Viagem foi incrível sounds unnatural in standard Portuguese.

Portuguese often uses articles in places where English might be more flexible. So when talking about a specific trip, use a viagem.

It would become:

As viagens foram incríveis. = The trips were incredible.

Notice all the changes:

• a → as
• viagem → viagens
• foi → foram
• incrível → incríveis

This is a good example of agreement across the sentence.