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I don't know where else to write that. But here: https://www.duolingo.com/skill/ro/Adjectives
Most of them, though, change have a different form in each case, like bun (good).
typo here ^ "change have a different form"
at the very end here https://www.duolingo.com/skill/ro/Verbs%3A-Present1 :
> Becul se inventează în 1897. | The light bulb is invented in 1879.**
double ** at the end