Por suerte, encontramos el indicio.

Yes. Por suerte is a very common expression meaning luckily, fortunately, or by luck.

• por = by / through / because of
• suerte = luck

So literally it is something like by luck. In natural English, though, you usually translate it as luckily or fortunately.

Other common expressions with a similar meaning are:

• afortunadamente = fortunately
• por fortuna = fortunately
• menos mal = good thing / luckily

In this sentence, Por suerte sets the tone for the whole statement: what happened was fortunate.

Because Por suerte is an introductory phrase commenting on the whole sentence, not part of the main action.

So in:

Por suerte, encontramos el indicio.

the main clause is:

encontramos el indicio

and Por suerte is an added comment meaning luckily.

In English, you often do the same thing:

• Luckily, we found the clue.
• Fortunately, we found the clue.

The comma helps separate that introductory comment from the main statement.

It can mean either one, depending on context.

Encontramos can be:

• present tense of encontrar for nosotros: we find
• preterite of encontrar for nosotros: we found

This is a very common feature in Spanish: for many -ar verbs, the nosotros form looks the same in the present and the preterite.

Examples:

• Hoy encontramos una solución. = Today we find a solution / more naturally Today we are finding a solution depending on context
• Ayer encontramos una solución. = Yesterday we found a solution

Without context, the form is ambiguous. Usually the surrounding words or the situation make the meaning clear.

Usually from context.

Spanish speakers rely on things like:

• time words: ayer, hoy, anoche, siempre, ahora
• surrounding sentences
• the situation being discussed

For example:

• Por suerte, ayer encontramos el indicio. → clearly we found
• Por suerte, siempre encontramos el indicio a tiempo. → clearly we find

If this sentence appears by itself, both readings are grammatically possible, though many learners are shown it as a past action: Luckily, we found the clue.

Spanish often uses articles more regularly than English does.

Here, el indicio means the clue / the indication / the sign. The article el shows that the speaker has a specific clue in mind.

Compare:

• Encontramos el indicio. = We found the clue / the piece of evidence
• Encontramos un indicio. = We found a clue / a piece of evidence

So el makes it definite and specific.

Also, indicio is a masculine singular noun, so it takes el.

They are similar, but not always identical.

Indicio usually means:

• indication
• sign
• clue
• piece of evidence

It often sounds a little more formal, investigative, or logical.

Pista is also often translated as clue, but it is more common in everyday contexts like riddles, mysteries, or detective stories.

Roughly:

• indicio = a sign or bit of evidence suggesting something
• pista = a clue that helps you solve something

Examples:

• La policía encontró un indicio. = The police found a piece of evidence / a clue
• Dame una pista. = Give me a clue / hint

So in many contexts they overlap, but indicio can sound a bit more formal or evidence-based.

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

The verb form encontramos already tells you the subject is nosotros (we), so saying nosotros is often unnecessary.

• Encontramos el indicio. = We found the clue
• Nosotros encontramos el indicio. = also correct, but more emphatic

You might include nosotros if you want contrast or emphasis:

• Ellos no encontraron nada, pero nosotros encontramos el indicio. = They didn’t find anything, but we found the clue.

So omitting the pronoun is the normal default.

In most of Latin America, indicio is pronounced approximately:

een-DEE-syo

A rough breakdown:

• in → like een
• di → dee
• cio → syo

Important point: in most Latin American Spanish, c before i or e sounds like s.

So:

• ci = see / syee-type sound
• ce = seh-type sound

That is why indicio sounds like in-DEE-syo, not in-DEE-kee-o.

Yes, absolutely.

Afortunadamente and por suerte are both natural here.

Compare:

• Por suerte, encontramos el indicio.
• Afortunadamente, encontramos el indicio.

The difference is mostly style:

• por suerte = a little more conversational and common
• afortunadamente = slightly more formal or polished

Both are correct.

Because introductory adverbial expressions often go at the beginning of the sentence.

That said, Spanish is flexible, and you can move por suerte around:

• Por suerte, encontramos el indicio.
• Encontramos el indicio, por suerte.
• Encontramos, por suerte, el indicio.

The first version is the most neutral and natural in many contexts. Putting por suerte first makes it clear right away that the speaker is commenting on the event as fortunate.

You would not use encontramos for that. You would usually use the imperfect:

• encontrábamos

Examples:

• Encontrábamos indicios con frecuencia. = We used to find clues frequently.
• Mientras buscábamos, encontrábamos pequeñas señales. = While we were searching, we were finding small signs.

So:

• encontramos = we find or we found
• encontrábamos = we used to find / we were finding

This is an important difference in Spanish because the tense tells you whether the action is viewed as completed or ongoing/habitual.

You would make both the noun and article plural:

• Por suerte, encontramos los indicios. = Luckily, we found the clues
• Por suerte, encontramos unos indicios. = Luckily, we found some clues

Changes:

• el → los
• indicio → indicios

So the pattern is:

• singular: el indicio
• plural: los indicios

It is common enough, but it is a bit more formal or specific than some everyday alternatives.

You are likely to hear it in contexts like:

• police or legal language
• mysteries and investigations
• formal explanations
• academic or analytical speech

In more casual speech, people might often say:

• pista = clue
• señal = sign
• prueba = evidence / proof, depending on context

So indicio is a useful and normal word, but it carries a slightly more precise or formal tone than some alternatives.