"Six, seven, eight."
Translation:A sé, a seacht, a hocht.
I just answered this without the 'a' counting particles, and while I was marked right Duolingo pointed out the alternate answer with the particle.
As far as I can tell, a speaker would use 'a' when counting, say, as the response to a question like "can you count to ten? -- an féidir leat a comhaireamh go deich?"
What kind of situation might a speaker say the sequence "sé, seacht, ocht" without the particle? While reading the sequence of digits '6 - 7 - 8' off of a credit card?