Questions & Answers about Gramatyka jest ważna, jeśli chcesz mówić poprawnie.
It is in the nominative case because it is the subject of the sentence.
The basic structure is:
- Gramatyka = the thing being talked about
- jest ważna = is important
So this is a straightforward subject + verb + adjective structure.
Jest is the 3rd person singular form of być (to be), so it means is.
In this sentence, it is perfectly normal to say:
- Gramatyka jest ważna
In some contexts, Polish can omit forms of to be, especially in the present tense in very informal or stylistic language, but with a sentence like this, jest is standard and natural.
So for a learner, it is best to treat this as the normal full sentence:
- Gramatyka jest ważna = Grammar is important