Learn Polish: Dzisiaj jest piękny dzień.

Adjectives in Polish must match the gender of the noun they describe. The word dzień (day) is a masculine noun, so the adjective takes the masculine ending -y to become piękny. If you were describing a feminine noun, you would use a different ending, like -a.

Why is the word order Dzisiaj jest piękny dzień instead of Dzisiaj dzień jest piękny?

Polish word order is very flexible. Both versions are grammatically correct, but Dzisiaj jest piękny dzień is the most natural way to express the English structure "Today is a beautiful day." Moving dzień earlier would change the emphasis, sounding more like "Today, the day is beautiful."

Is there a trick to pronouncing the dzi in dzisiaj and dzień?

Yes! When the letters d and z are followed by an i, they merge into a single soft sound. It sounds a bit like the "j" in the English word "jeep" but even softer. In dzień, the i just softens the consonant and connects it to the e, so you don't pronounce a separate "ee" vowel sound.

Why isn't there a word for "a" before piękny dzień?

Polish does not have articles like "a", "an", or "the". You simply leave them out. The context tells you whether it means "a beautiful day" or "the beautiful day", so the phrase piękny dzień does all the work on its own.