Please accept this short diatribe with the reassurance that this sparsely-updated blog won’t devolve into a linguistics tome.
That said, I feel the need to clarify the use of the English indefinite article, if nothing more than for the benefaction of anglophone humanity in general. This is prompted by a recently surfaced FAQ on dictionary.com, which got the subtleties of the rule sorely incorrect. And subsequently ignored my intercessions to rectify their misinformation. As I’m sure you can see, I have no choice but to take matters into my own hands.
We all know that ‘a’ goes before words that begin with a consonant sound (thus including vowel words such as ‘user’) and ‘an’ goes before words that begin with a vowel sound (thus including consonant words such as ‘hour’ and before acronyms that start with a vowel sound such as ‘XYZ’).
Here’s the catch: ‘an’ is also used before multisyllabic words that begin with ‘h’ when the stress is not on the first syllable. This is why we say ‘an historic event’ or ‘there is always an however’. Similarly, you cannot say ‘an house’ or ‘an housing project’ because the former is monosyllabic and the latter is disyllabic with initial stress (savvy?). I’m sure you’ve heard ‘an however’ but you might not have known why and you might not have known that it can be extended to other ‘h-’ words such as ‘an Hungarian goose’ or ‘an humanitarian crisis’. The possibilities are…well, not endless but greater than you’d imagine.
Now go forth and use your superior knowledge of English grammar to make everyone else know that you’re smarter than them. That is all.