Compramos una botella de tinto.

It can mean either one.

With -ar verbs, the nosotros form in the present tense and the preterite looks the same:

• compramos = we buy
• compramos = we bought

So Spanish relies on context to make the time clear.

For example:

• Cada viernes compramos una botella de tinto. = Every Friday we buy a bottle of red wine.
• Anoche compramos una botella de tinto. = Last night we bought a bottle of red wine.

On its own, the sentence is grammatically ambiguous.

Because Spanish often leaves out subject pronouns when they are not needed.

The ending -amos already tells you the subject is we. So:

• Compramos una botella de tinto.
• Nosotros compramos una botella de tinto.

Both are correct, but the version without nosotros sounds more natural in many situations.

You would add nosotros for:

• emphasis
• contrast
• clarity

Example:

• Ellos pidieron cerveza, pero nosotros compramos una botella de tinto.

Because botella is a feminine noun.

In Spanish, articles have to match the noun’s gender:

• el / un for masculine nouns
• la / una for feminine nouns

So:

• una botella
• la botella

Even though many feminine nouns end in -a, that is only a pattern, not the rule itself. The important thing is that botella is feminine, so it takes una.

Here de means of.

This is a very common Spanish pattern:

container + de + contents

Examples:

• una taza de café = a cup of coffee
• un vaso de agua = a glass of water
• una botella de vino = a bottle of wine
• una botella de tinto = a bottle of red wine

So de links the container to what is inside it.

Because tinto can be used by itself as a shortened way to mean red wine, when the context is clear.

The full phrase is:

• vino tinto = red wine

But native speakers often shorten it to:

• tinto

This is similar to how English sometimes shortens expressions when the meaning is obvious from context.

So both are possible:

• Compramos una botella de tinto.
• Compramos una botella de vino tinto.

The second one is more explicit. The first one is more concise and natural in the right context.

No. It can vary by region.

In many places, tinto can mean red wine as a shortened form of vino tinto.

But in Colombia, tinto very commonly means black coffee.

So regional context matters a lot.

In this sentence, una botella de tinto strongly suggests red wine, because a bottle fits wine much better than coffee in normal usage.

Because in Spanish, when you talk about a substance or type of thing in a general way, you often use de + noun without an article.

So these are normal:

• una botella de vino
• una taza de café
• un vaso de leche
• una botella de tinto

You would use del (de + el) only if you mean a specific red wine that has already been identified.

For example:

• Compramos una botella del tinto chileno que nos recomendaron.

That means a bottle of the Chilean red wine they recommended to us.

Originally, tinto is part of the phrase vino tinto, where it functions as an adjective describing vino.

• vino tinto = red wine

But in una botella de tinto, the word vino is understood and left out. So tinto is acting like a noun here.

This is sometimes called ellipsis: a word is omitted because it is obvious from context.

So:

• vino tinto → full expression
• tinto → shortened noun-like use

Yes, absolutely.

That version is:

• more explicit
• often clearer for learners
• sometimes more universally understood

So both are correct:

• Compramos una botella de tinto.
• Compramos una botella de vino tinto.

If you want to avoid regional ambiguity, especially because tinto can mean other things in some countries, vino tinto is the safer choice.

No. It is pronounced the same way in both cases.

That is why the sentence can be ambiguous without context.

The distinction is grammatical, not pronunciation-based:

• compramos = present we buy
• compramos = preterite we bought

Native speakers understand the intended meaning from context, time words, and the surrounding conversation.

Sometimes, yes.

Spanish often uses the simple present to talk about actions happening now, especially in conversation. So depending on context, compramos might mean:

• we buy
• we’re buying

But if someone wants to make the ongoing action very explicit, they can say:

• Estamos comprando una botella de tinto.

That specifically means We are buying a bottle of red wine.

So the simple form is flexible, and context decides the exact meaning.