Questions & Answers about Powietrze w lesie jest czyste.
Why does the word for forest change to lesie here?
Because we are saying in the forest, the preposition w (in) requires the Locative case. The basic dictionary word for forest is las. To form the Locative, the vowel a changes to e, and the consonant s softens, resulting in lesie.
Why does the adjective czyste end in -e?
The adjective must match the noun it describes. It is describing powietrze (air), which is a neuter noun. The standard ending for a neuter adjective in the Nominative (subject) case is -e.
How do I know the gender of powietrze?
Nouns that end in -e are almost always neuter in Polish. This is a very reliable pattern that includes other common words you have learned like śniadanie (breakfast) and mieszkanie (apartment).
How would I change this sentence to say 'The air in the forest should be clean' using our current lesson?
You would add the neuter form of should, which is powinno (matching the neuter noun powietrze), and change jest to its dictionary infinitive form być (to be). The sentence becomes: Powietrze w lesie powinno być czyste.