Shouldn't this be "Eu inicio à cerimônia"?
Iniciar doesn't take a preposition. It's a monotransitive verb (in Portuguese trantitivo direto). But if the sentence was "Eu dei início à cerimônia", then it would need the crasis.
And yes, it is an error if you put it.
Is there a list of (Direct/Indirect) Transitive verbs in Portuguese to read in Duolingo? At least the most common...
No...unfortunately! You have to make some research on the web...
That would be "Eu inicio a a cerimônia" but "iniciar" does not need the preposition "a" so Duolingo's sentence is correct I think.
Yes, a+a = à :)
In all other places I've seen so far, it is prepositioned by "a." But of course that does not make it a sure thing.
Oh, dear. I didn't mean to imply you weren't aware that a+a=à and I'm sorry if it came across that way.
Davu is correct. Iniciar requires no preposition, different from "vou à cerimônia" where its use is mandatory.
Ok, but is it an error when a preposition is used? Duolingo has done it twice to me so far.
We're definitely in need of Paulenrique or someone else who knows if it's mandatory, one of those random Portuguese things, or a Duolingo error :D