Questions & Answers about Metal jest droższy niż plastik.
How do we form the comparative word droższy?
It comes from the basic adjective drogi (expensive). To make it comparative (more expensive), the -gi ending changes to -ższy. This g to ż sound change is a very common pattern in Polish comparatives.
Does the word niż change the grammatical case of the word plastik?
No. The word niż (than) acts like a mirror for grammatical cases. Because the first item being compared (metal) is the subject of the sentence and in the basic nominative case, the second item (plastik) also stays in the nominative case.
Why does droższy end in -y instead of -a or -e?
Comparative adjectives still have to match the gender of the noun they describe. Since metal is a masculine noun, we use the masculine comparative form droższy. If we were comparing a feminine noun, it would be droższa.