In this type-what-you-hear question she said Dè th' ann?, so that is what I put. She definitely did not say Dè a th' ann?. I would normally write Dè th' ann?. That can be argued about. But there is no doubt what she said, so what I wrote should be accepted, and you could even argue that Dè a th' ann? should not be accepted.
But dè th’ ann? and dè a th’ ann? are exactly the same thing in Gaelic, just as càite a bheil? vs càit a bheil? (and it seems there is quite a few people writing càite bheil? too).
The relative particle a is a never-stressed reduced /ə/ and so it is elided in speech when in contact with other vowels. Dè a always sounds the same as just dè, just as cò a has the sound of cò, etc. Thus dè a th’ ann, dè th’a ann, dè a tha ann, etc. are all different ways to write down the same spoken words. Grammatically the tha here is in a relative clause, so if you stick to writing down all relative particles, even the silent ones, then it must be dè a th’…?.
So no, dè a th’ ann should be accepted as that is, I believe, the most common way to write it down in Gaelic. The question I don’t have any answer to is whether the spelling dè th’ ann should be accepted or not.
I see the course uses the reduced spelling (with omitted particle a) only in one expression: dè tha dol? instead of full dè a tha (a’) dol? (as again, the short it the most common spelling used).
Also, there are recordings by one (and as far as I can tell, only one) speaker where the a is fully pronounced as a separate syllable (dè a th’ann pronounced as [dʒeː.ʔə.haun]) – but I think that’s just an artifact of too careful clear slow recording for learners and not the way they would actually say such a sentence (but maybe I’m wrong?). The other speakers all have [dʒeː.haun], two syllables.
Weird. I thought I got over 500k results for "dè tha seo" once too but then could not repeat that – Google always giving me only 50 hits for the short version with quotes.
Anyway – I won’t argue about that any more. I don’t mind the short version being accepted too if that’s how Gaelic is being written too.
But I definitely think that the long version should be accepted since that’s the default taught in the course.
EDIT: ROTFL, Google was being helpful and decided to ‘omit some entries similar to shown results’ truncating the results list from over 500k to exactly 50. When I forced it to show omitted results I see 500k again.