no. adjectives have to match the noun so they are already plural even if there is only one door. 99% of sentences number of doors is left amibigous. only if you actually add numeral/ quantifier you can determine how many doors are there
That's very interesting. Thank you so much for your input. I wish Polish Duo had some sort of comments/instructions per each topic instead of letting all the learners swim in the deep ocean by themselves !