A avaliação psicológica e o exame toxicológico estão prontos.

Because Portuguese nouns have grammatical gender.

• avaliação is a feminine noun, so it takes a
• exame is a masculine noun, so it takes o

This gender affects not only the article, but also any adjectives that describe the noun:

• avaliação psicológica
• exame toxicológico

Grammatical gender in Portuguese does not necessarily match biological sex or any logical category, so it often has to be learned with each noun.

In Portuguese, adjectives often come after the noun, especially in neutral, descriptive language.

So:

• avaliação psicológica = psychological evaluation
• exame toxicológico = toxicological exam

This is more natural in Portuguese than putting the adjective first. In some cases, adjective position can change nuance, but here the standard order is noun + adjective.

Because adjectives must agree with the noun they describe in gender and number.

• avaliação is feminine singular → psicológica
• exame is masculine singular → toxicológico

So the endings change to match:

• masculine singular: -o
• feminine singular: -a

This agreement is a basic feature of Portuguese grammar.

Because the subject is compound: there are two things being talked about:

• a avaliação psicológica
• o exame toxicológico

When two nouns are joined by e (and), the verb normally goes in the plural.

So:

• A avaliação psicológica está pronta. = only one item
• O exame toxicológico está pronto. = only one item
• A avaliação psicológica e o exame toxicológico estão prontos. = both items

Because prontos is agreeing with both nouns together.

When a masculine noun and a feminine noun are combined in Portuguese, the normal default for plural adjective agreement is masculine plural.

Here you have:

• a avaliação = feminine
• o exame = masculine

Together, they take:

• prontos = masculine plural

If both nouns were feminine, you would use prontas.

For example:

• A avaliação e a análise estão prontas.

It agrees with the whole compound subject:

A avaliação psicológica e o exame toxicológico

Since that subject is plural and mixed gender, the adjective becomes masculine plural: prontos.

This is similar to how the verb also agrees with the whole subject:

• subject: two things
• verb: estão
• adjective: prontos

Portuguese often uses estar for a current state or condition.

Here, estar pronto means to be ready.

So estão prontos means they are currently ready/available/completed.

Using ser here would sound wrong in standard Portuguese, because readiness is seen as a temporary state, not a permanent characteristic.

Compare:

• está pronto = is ready
• é pronto = generally not natural in this context

Yes. Those forms change the nuance a little.

• estão prontos = are ready
• já estão prontos = are already ready
• ficaram prontos = became ready / ended up ready
• foram concluídos = were completed, more formal and more focused on completion

So the original sentence is a very natural way to say that both items are now ready.

Portuguese uses definite articles much more often than English.

In many contexts, Portuguese prefers:

• a avaliação
• o exame

where English might omit the.

So even if English sounds more natural without an article in some contexts, Portuguese often keeps it. This is especially common when referring to specific known items, documents, procedures, or things already understood in context.

Yes. That is grammatically correct.

The order can change depending on what the speaker wants to mention first or emphasize first. The agreement stays the same:

• O exame toxicológico e a avaliação psicológica estão prontos.

Because the subject still contains one masculine noun and one feminine noun, the adjective remains prontos.

You would make both the verb and adjective singular.

Examples:

• A avaliação psicológica está pronta.
• O exame toxicológico está pronto.

Notice the agreement:

• feminine singular → pronta
• masculine singular → pronto

So the plural forms in the original sentence are there because it refers to both items.

Estão is pronounced roughly like eh-STOWN, but with a nasal sound.

The ã makes the vowel nasal, which means air flows through the nose while saying it. This nasal sound is very common in Portuguese.

A rough breakdown:

• es = like es in set
• tão = nasalized tow, not a plain English ow

The tilde ~ over ã marks nasalization.

A few useful points:

• avaliação has nasal -ção, a very common ending in Portuguese
• psicológica has stress on ló
• exame sounds roughly like eh-ZAH-mee
• toxicológico also has stress on ló

Very roughly:

• avaliação → ah-vah-lee-ah-SOWN
• psicológica → psee-koh-LAW-zhee-kah (Brazilian pronunciation)
• exame → eh-ZAH-mee
• toxicológico → toh-ksee-koh-LAW-zhee-koh

These are only approximations, but they can help at the beginning.

In real usage, it can often imply either, depending on context.

For example, this sentence could mean:

• the procedures are completed
• the reports are ready
• the results are available

Portuguese often leaves that understood from the situation. If someone at a clinic or office says this, they usually mean the relevant items are ready for the next step—pickup, review, submission, or consultation.