Es importante revisar el estado del puente cada año.

Because ser is used for general qualities, definitions, and evaluations, while estar is used for temporary states or conditions.

Here, Es importante means It is important, which is a general judgment about the action that follows. So Spanish uses ser:

• Es importante revisar... = It is important to check...

Using estar here would sound wrong in standard Spanish.

After Es importante, Spanish normally uses the infinitive when speaking generally about an action.

So:

• Es importante revisar... = It is important to check/review...

This works like English to review.

Compare:

• revisar = to inspect / to check
• revisa = he/she checks or check! (command)
• revisando = checking

So the infinitive is the correct form here.

Here revisar means something like to inspect, to check, or to examine.

With a bridge, revisar suggests checking its condition carefully, not just casually looking at it.

Depending on context, English translations could be:

• to inspect
• to check
• to review
  (though inspect or check sounds more natural here)

In this sentence, el estado means the condition or the state of the bridge.

So:

• el estado del puente = the condition of the bridge

Although estado can also mean state in other contexts, here it clearly refers to physical condition.

Spanish often uses the definite article more than English does.

Here, el estado refers to the specific condition being evaluated, so the condition is natural in Spanish:

• revisar el estado = to check the condition

Leaving out el would be ungrammatical here.

Because de + el contracts to del in Spanish.

So:

• de + el = del

That is why:

• el estado del puente = the condition of the bridge

This contraction is mandatory. You normally cannot say de el puente.

A similar contraction is:

• a + el = al

Because Spanish normally needs the article here when referring to a specific noun.

• del puente = of the bridge

Without the article, de puente would sound incomplete or unnatural in this sentence.

So the structure is:

• el estado del puente
• literally: the condition of the bridge

Cada año means every year or each year.

Yes, todos los años is also possible, and it means every year too.

So both are natural:

• cada año
• todos los años

A small difference in feel:

• cada año can sound a bit more like each individual year
• todos los años can sound a bit more like every year in a repeated sense

In most everyday contexts, they are very close in meaning.

Spanish often places time expressions like cada año near the end, especially when they modify the whole action.

So:

• Es importante revisar el estado del puente cada año

is a very natural word order.

You could move it for emphasis, but the original order is the most neutral and standard.

Yes. A more explicit version would be:

• Es importante que se revise el estado del puente cada año.

This means roughly the same thing, but the structure is different.

• Es importante revisar... = general statement with an infinitive
• Es importante que se revise... = more formal or more focused on the action being carried out

Why the subjunctive? Because es importante que... expresses evaluation or necessity, which triggers the subjunctive.

Not all Spanish adjectives change between masculine and feminine.

Importante ends in -e, so it usually stays the same:

• Es importante
• La revisión es importante
• Los controles son importantes

It only changes for number:

• singular: importante
• plural: importantes

Yes, it is basically an impersonal construction.

• Es importante... = It is important...

The es does not refer to a specific person or thing. It works like English it is in a general statement.

This is a very common pattern in Spanish:

• Es bueno descansar.
• Es necesario estudiar.
• Es importante revisar el estado del puente cada año.

This sentence sounds completely natural in Spain and is also understood everywhere else in the Spanish-speaking world.

Nothing in it is especially regional. In Spain, it would be a standard and neutral sentence.

A speaker from another country might choose a slightly different verb in some contexts, such as inspeccionar instead of revisar, but revisar is perfectly normal and widely used.