I think this is random, you can drop whenever you want:
Você tem tesoura? / Você tem uma tesoura? (Do you have scissors?).
Quer tomar café? / Quer tomar um café? (Do you want coffee / some coffee?).
Ok, not whenever you want. If you are telling someone a story and there's a sentence like "A girl was walking on the street", you can't say "Menina estava andando na rua", it has to be "Uma menina estava andando na rua". Because the girl is unknown. But an object is always known even if you've never seen this particular one. I don't know if that's understandable. xD
why you can not skip the voice record part on the laptop verison of Duolingo? I tried to skip the questions with recordings as Duolino was not identifing my voice. Because of one mistake on my side and 3 voice recording questions I have to repeat the whole thing again. thats not soo cool :/
Well, looks like I have it all turned on; but it's never asked me to say anything. Does that work on a mac, or is that a mac / PC / android difference? Or am I still being dense? I only get questions to translate in writing, and questions that duolingo speaks for me to type in portuguese. Nothing asking me to speak. Where should those questions be, in the lessons? I visit brazil in two weeks…It would certainly help...
Nope. I don't even know where / what questions should have a microphone component, which makes it hard to guess where I should be looking! I also tried firefox, no luck. Also sent a problem report.
As I'm literally walking distance from headquarters in PGH--about a mile and a half--I'm tempted to walk over and knock on the door. See if I can trade any free help for free help, that sort of thing. "PhD, willing to mop floors for the sake of feeling less idiotic." ; )