Thank you all for your thoughts. They’re a big help.
I think he must have been talking about when the indefinite noun is qualified by an adjective. I just remember that it confused me.
He told us as well that ‘ag léamh’ is incorrect so I’ll ask him next week to explain why it is that ‘ag léamh’ is wrong. He said it’s ‘a léamh’ and that ‘ag léamh’ is a common mistake.
We do be translating legislation and so we’re often busy and I forget to ask him questions I have written down in my notebook.
I’ll ask him next week and find out exactly what he meant in both cases.
Thanks again.