Learn Polish: Jest cicho, ale w lesie słychać wilka. - It's quiet, but you can hear a wolf in the forest.

Polish uses the special impersonal word słychać for this. It literally means 'can be heard' or 'one can hear,' so you do not need a subject pronoun. It simply describes a general sensory experience in the environment.

Why does the word for wolf change to wilka here?

The word słychać requires the object being heard to be in the accusative case (the direct object). Because a wolf (wilk) is a living animal (a masculine animate noun), its accusative ending is -a, making it wilka.

Why do we say Jest cicho instead of using the adjective cichy (quiet)?

In Polish, when you describe general states of the environment, weather, or atmosphere without a specific subject (like 'It is quiet' or 'It is cold'), you use the verb być (to be) plus an adverb. Cicho is the adverb form of cichy.

Why does las (forest) become lesie?

It is in the locative case because it follows the preposition w (in) to show a static location. The word las has a special spelling change: when adding the locative ending -e, the vowel a changes to e, and the s softens, resulting in lesie.