La policía vigila la entrada.

In Spanish, la policía is often treated as a singular collective noun meaning the police force or the police as an institution.

That is why the verb is singular: vigila, not vigilan.

If you want to talk about individual police officers, you would usually say los policías.

• La policía vigila la entrada = the police force is watching the entrance
• Los policías vigilan la entrada = the police officers are watching the entrance

Yes. Policía can refer to a police officer, and the article shows the gender:

• el policía = the male police officer
• la policía = the female police officer

So La policía vigila la entrada could also mean The policewoman watches the entrance.

Usually, context tells you which meaning is intended: the police force or the policewoman.

Vigila is the third-person singular present tense of vigilar.

It matches the subject la policía, which is grammatically singular here.

The verb forms are:

• yo vigilo = I watch / I monitor
• tú vigilas = you watch
• él / ella / usted vigila = he / she / you watch

So:

• La policía vigila... = the police / the policewoman watches...

Vigilar means something like:

• to watch
• to keep watch over
• to monitor
• to guard
• to keep an eye on

It is not exactly the same as mirar, which usually means to look at.

So:

• mirar la entrada = to look at the entrance
• vigilar la entrada = to watch/guard/monitor the entrance

In this sentence, vigilar suggests supervision or security, not just looking.

Because Spanish often uses the simple present for actions happening now, especially when the context is clear.

So La policía vigila la entrada can mean:

• The police watch the entrance
• The police are watching the entrance

If you say La policía está vigilando la entrada, that puts more emphasis on the action being in progress right now.

Both are possible, but the simple present is very common and natural in Spanish.

La entrada means the entrance, so it refers to a specific entrance that is known in the situation.

Spanish uses the definite article when the speaker and listener can identify the thing being talked about.

• la entrada = the entrance
• una entrada = an entrance

So:

• La policía vigila la entrada = the police are watching the entrance
• La policía vigila una entrada = the police are watching an entrance

The first one sounds more natural if there is one obvious entrance being discussed.

Because la entrada is a thing, not a person.

The personal a is generally used before a specific human direct object, and sometimes animals treated as personal beings.

Examples:

• Veo a María = I see María
• La policía vigila la entrada = the police watch the entrance

Since entrada is an inanimate object, there is no personal a.

In standard Spain Spanish, policía is pronounced roughly po-li-THI-a.

Two useful points:

• The stress falls on -cí-, because of the accent mark: poliCÍa
• In most of Spain, c before i sounds like the th in think

So:

• policía → po-li-THI-a

However, in some parts of Spain, and in Latin America, it sounds more like po-li-SI-a.

Because in Spanish, g before e or i is pronounced like a strong throaty sound, similar to the Spanish j.

So vigila is pronounced roughly bee-HEE-la in Spain.

This surprises many English speakers, because they expect a hard g sound like in go. But that only happens before a, o, or u:

• gato = hard g
• golpe = hard g
• vigila = throaty g/j sound

The normal, neutral order is:

subject + verb + object

So:

La policía vigila la entrada.

Spanish word order is more flexible than English, though. You can change it for emphasis, style, or context.

For example:

• La entrada la vigila la policía.

That gives extra focus to la entrada.

But for a learner, the original sentence is the most standard and natural pattern.

No. Entrada can have several meanings depending on context, including:

• entrance
• entry
• ticket
• starter or first course in some contexts

But in La policía vigila la entrada, the meaning is clearly entrance because vigilar fits that meaning naturally.

So here, la entrada means the place where people go in.