"Peter's father is not young."
Translation:पीटर के पिता जवान नहीं हैं।
July 29, 2018
Yes. It looks like the adjectives that end in "a" (sorry, I don't have devanagari keyboard) decline like you would expect. Adjectives that end in other letters don't decline. https://hindilanguage.info/hindi-grammar/adjectives/