Liberamos al animal.

Because al is the mandatory contraction of a + el in Spanish.

Here, the a is the so-called personal a, and el is the masculine singular definite article.

So:

• a + el = al
• a + la does not contract
• a + los does not contract
• a + las does not contract

Examples:

• Veo al perro.
• Ayudamos a la niña.

So Liberamos al animal is the correct form, not Liberamos a el animal.

This is because Spanish often uses the personal a before a specific direct object that is animate or treated as a being.

Since animal refers to a living creature, Spanish commonly uses a with it, especially when it is a specific animal.

Compare:

• Liberamos al animal. = a specific animal
• Estudiamos animales. = animals in general, no personal a

With animals, the use of the personal a can depend somewhat on whether the animal is being treated as an individual being rather than as a category or object. In this sentence, it sounds like a specific animal, so al animal is natural.

Because animal is a masculine noun: el animal.

A noun beginning with a does not automatically take la or become feminine. The gender has to be learned with the noun.

Examples:

• el animal
• el árbol
• el avión

You may know that some feminine nouns use el before a stressed a- sound, like el agua or el águila. But that is a different rule. In animal, the noun is simply masculine.

Liberamos can mean two different things:

• present tense: we free / we release
• preterite: we freed / we released

So this form is ambiguous by itself.

Examples:

• Cada año liberamos animales heridos.
  = present: we release
• Ayer liberamos al animal.
  = preterite: we released

Only the context tells you which meaning is intended.

Because in Spanish, some verb forms are spelled exactly the same in the present and the preterite for -ar verbs in nosotros.

So:

• liberamos = present or preterite
• hablamos = present or preterite
• compramos = present or preterite

Spanish relies on context, not spelling, to distinguish them in these cases.

Because Spanish often omits subject pronouns when the verb already shows who is doing the action.

Liberamos already tells you the subject is we.

So:

• Liberamos al animal.
• Nosotros liberamos al animal.

Both are correct, but the version without nosotros is more neutral and more common.

You would add nosotros mainly for:

• emphasis
• contrast
• clarity

For example:

• Nosotros liberamos al animal, no ellos.

Yes. Since el animal is a masculine singular direct object, you can replace it with lo.

So:

• Liberamos al animal.
• Lo liberamos.

Both are correct.

You can also use both together for emphasis or certain sentence structures:

• Al animal lo liberamos ayer.

That structure is possible, especially when fronting the object, but the most basic version is still:

• Liberamos al animal.

Yes, but Liberamos al animal is the most straightforward and neutral order: verb + object.

Spanish word order is more flexible than English, so other versions are possible depending on emphasis:

• Liberamos al animal. = neutral
• Al animal lo liberamos nosotros. = emphasis on the animal
• Nosotros liberamos al animal. = emphasis on we

So the original sentence is the normal, standard way to say it.

The infinitive is liberar.

This sentence uses the first person plural form: nosotros.

For a regular -ar verb, the endings are:

Present

• yo libero
• tú liberas
• él/ella/usted libera
• nosotros liberamos
• vosotros liberáis
• ellos/ellas/ustedes liberan

Preterite

• yo liberé
• tú liberaste
• él/ella/usted liberó
• nosotros liberamos
• vosotros liberasteis
• ellos/ellas/ustedes liberaron

That is why liberamos can belong to either tense.

A careful Spain Spanish pronunciation would be approximately:

lee-beh-RAH-mos al ah-nee-MAL

A few useful pronunciation notes:

• b in liberamos is pronounced like a soft Spanish b/v sound, not exactly like a strong English b in every position.
• r in liberamos is a single tapped r, not a long English r.
• al is pronounced as one short word.
• The stress is on -ra- in liberamos and on the final syllable in animal.

So the rhythm is roughly:

li-be-RA-mos al a-ni-MAL