Learn Hardcore Spanish (Spain): Después de haber llovido, el aire se siente fresco. - After it has rained, the air feels fresh.

“Después de” is a preposition, so if it’s followed directly by a verb, that verb must be in the infinitive. To show that the action is completed before the main clause, Spanish can use the perfect infinitive: haber + past participle → haber llovido.
“Después de llover” is also correct; it’s the simple infinitive. It often sounds a bit more general or habitual. “Después de haber llovido” highlights completion a bit more explicitly and can sound a touch more formal.
With a finite verb, you must add “que”: después de que llovió/ha llovido. Those are also correct and common.

Is “después de llover” wrong here?

No. Después de llover, el aire se siente fresco is perfectly natural. The difference from “después de haber llovido” is subtle: the perfect infinitive emphasizes the prior completion of the rain; the simple infinitive is more neutral or generic. In everyday speech, many speakers would use either without worrying about nuance.

Can I say “después que” instead of “después de que”?

In Spain, the standard form is después de que. Después que is heard in parts of Latin America and is accepted by the RAE, but in Spain it can sound nonstandard. If your goal is Peninsular Spanish, use después de que with a clause, or después de + infinitive.

What does the “se” do in “se siente”?

It turns sentir into the pronominal verb sentirse, which works like a linking verb meaning “to feel (as), to be perceived as.”

El aire se siente fresco ≈ “The air feels (is perceived as) cool.”
Without “se,” sentir is transitive: Siento el aire fresco = “I feel the cool air.” So you need the pronominal form to say that the air itself “feels” a certain way.

Could I say “está fresco” or “hace fresco” instead of “se siente fresco”?

Yes, all are possible, with slight differences:

El aire está fresco states a property/state.
Hace fresco is the very common weather expression in Spain: “It’s cool (out).”
El aire se siente fresco emphasizes how it’s perceived or how it “feels” to you.
All sound natural; for general weather talk, “Hace fresco” is extremely idiomatic.

What’s the difference between “fresco” and “frío” here?

Fresco = “cool,” pleasantly or mildly cold.
Frío = “cold,” noticeably colder, potentially uncomfortable.
So after rain, saying the air is fresco is typical; frío would mean it feels cold.

Why is it “fresco” (masculine singular)? Does it agree with “aire”?

Yes. Aire is masculine singular in Spanish (el aire), so the adjective must match: fresco. If the noun were feminine plural, you’d change the adjective accordingly (e.g., “las noches están frescas”).

Do I need the article “el” before “aire”? Could I drop it?

You need it here. Spanish commonly uses the definite article with generic or abstract nouns where English would omit it. El aire is the natural way to refer to “the air” in general. Bare “aire” without an article would sound odd in this sentence.

Can I move the time phrase to the end: “El aire se siente fresco después de haber llovido”?

Yes. Both orders are fine:

Después de haber llovido, el aire se siente fresco.
El aire se siente fresco después de haber llovido. Placing the time phrase at the end is very common and often feels more neutral.

Why is there a comma after the introductory phrase?

Spanish typically uses a comma after a fronted adverbial phrase, especially if it’s more than a couple of words or could momentarily confuse the reader. “Después de haber llovido,” is a clear unit, so the comma is recommended. If you put the phrase at the end, no comma is needed.

Is “llovido” an irregular form? Anything special about “llover”?

Llover is impersonal: it’s used in the 3rd person singular (llueve, llovió, ha llovido…).
The past participle llovido is regular.
So “haber llovido” is simply the perfect infinitive of an impersonal verb: “to have rained.”

How would Spaniards phrase this idea in other natural ways?

Common alternatives include:

El aire está fresco (después de llover).
Hace fresco (después de llover).
Se respira un aire fresco (después de llover).
Tras llover / Tras haber llovido, el aire está fresco. (“Tras” is a concise synonym of “después de” and is common in Spain.)