"The bicycles are new."
Translation:Las bicicletas son nuevas.
This should be accepted. I rode my bicycle from Texas to Ushuaia from 2013 to 2015 and it was almost exclusively referred to as "bici" in Mexico, Central and South America. I reported this to Duolingo. Maybe in the future it will be accepted.
The 'newness" is part of what the bicycles are. The ser= permanent and estar= temporary thing is often overdone. I say 'soy joven' even though I will someday be old.
Jaja - all this time, with all of your wisdom...I assumed you were a senior!
I guess that makes sense. I actually overthought this one: I first typed in "son" and just as I was about to press enter I though "what if it's estan instead." "son" sounded right, but I convinced myself it should be estar...
How to be sure of what sounds right and what doesn't? If the temporary/permanent thing is not the key guideline, what is?