Because I'm such an incredible nerd, I just got to thinking about our favorite article twins, a and an. The general rule is to use an in front of a vowel, a in front of a consonant. So it would be a girl, a boy, a hour, an apple, an envelope, an utility.
But those aren’t all right, are they? In fact, spell check is telling me to correct “a hour.” As it should!
To be more specific, a is supposed to be used in front of a consonant sound, while an is used in front of a vowel sound. Though a vowel, u started words often sound like consonants, like the word utopia (you-tope-ee-ah). An utopia doesn’t sound right. But an umlaut (uhm-lout) does!
And that h. Always a trouble maker. Despite what Jon Stewart says, it’s a historical event, not an historical event. The only reason hour comes with an an (I can’t believe I just wrote that…) is that it sounds like “an our.” Another example is the adopted French word hors d’oeuvre, or heir. Always an an, never an a.
Remember: it’s the sound, not the start. : )