I don't really get the 'spacious' part. It sounds like "uasa3a" but I think I see "waasi3a". Could anyone explain the spelling. Kasra under س should render a syllable -si-, but I can't hear it. Is the first و the vowel uu or the semivowel w? Is the following ا a vowel aa or a holder for ء?
There is indeed an -si- sound, but it's less prominent than it should be. You can listen to a better pronunciation by tapping/clicking on the speaker icon under the Arabic translation of this sentence in Google Translate here https://translate.google.com/#view=home&op=translate&sl=en&tl=ar&text=a%20spacious%20room
Playing the audio again would make it speak slower.
There is no implied hamza here, as for و I’ve never analyzed it this deeply so I’m not sure. All these problems go away after a while if you listen to Arabic recordings every day while following the letters with your eyes (So you'd need transcripts). Forget the meaning for now, just train your eyes to keep following the letters while noticing the sound being made. You'll find this a bit overwhelming at first, but give it 2 weeks of daily practice (10 minutes per day are enough) and you'll start feeling the benefits. Keep doing this throughout your learning, and the long term benefits will be immense, as you'd be much more familiar with the sounds of the language and its structure (unconsciously) and your brain will be a lot more ready to absorb the information once you get to it in the Duolingo tree (or using any other resource).
If you'd like general tips on learning languages, I recommend you read my previous posts on the subject, which you can find by following these links:
Never mind! There is a standard for MSA. I have an excellent article about stress, but I couldn't find it right now. I'm rather sure that the stress falls on the long aa (i.e.) alif in this case. I understand that this is not very crucial in Arabic, as MSA is not a naturally spoken language and everybody is talking their own dialect with its own particular variations in grammar, pronunciation and stress. Thanks anyway SamirShaker.
Yes, I have a pocket dictionary that says that, too, when I look up "wide" in the English to Arabic section. But, the opposite of wide is narrow, the opposite of big is small, and the opposite of spacious, or roomy, is cramped. Spacious and wide are not the same thing in English. Google Translate gives فسية/fasiha as the best translation of "spacious". فسية is not even in my 440 page pocket dictionary, though. I checked a few online dictionaries and I get both words showing up, but different words in different dictionaries, plus a few more words thrown in. Maybe it's a dialect thing. ??? Perhaps a bilingual Arabic/English speaker could tell us more about this.