I guess I'm older than you are. I was taught that either was appropriate. A little googling showed me that in the US, up until about the late 1940s, actual usage was 50/50. Then it started to trend to mainly using "A" before words beginning with "h." It is speculated that there might be a regional difference. It some parts of the country there is a tendency to drop the "h" in words of 3 or more syllables, making the use of "AN" more natural.
One fundamental question which still eludes me is how much of this is due to Communist agitation. They are past masters at this kind of process, they have had plenty of practice, and they may think conditions are now ripe here for the next phase of the "armed struggle". We will see.
It was the nuns that ensured I learned that basic grammar rule. Boy howdy did they ever! < BG >
I’m in MA and use both
I would say “A history lesson” but would also say “An historical event”.
I didn’t realize that I did that until just this moment. :-)
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