‘A’ vs. ‘An’–the why and how

It’s been a while since I’ve updated anything at all, and even longer since I’ve posted anything about writing. I’ve taken on a new project which I’ll probably talk about more once I have something to show for it. For now, all you get is a pedantic rant about one of the smallest yet most irksome mistakes I see in writing.

Putting an ‘a’ where there should be an ‘an’ might not seem like such an unforgivable offense at first. It doesn’t obscure the meaning of the sentence as other grammatical mistakes may. But every time I see or hear this mistake it grates on my nerves like nails on a chalkboard.

It’s not just a stylistic or pedantic reason that this particular mistake bothers me. Coming across this mistake robs the entire passage of any narrative momentum it may have had, making you stop dead in your tracks much the same way a misplaced comma does. It’s one of the little things that can suck you right out of whatever you’re reading.

What is the rule?

Most–if not all–of you have probably heard this rule before. If a word begins with a consonant it gets ‘a’ while a word that begins with a vowel gets ‘an.’

However, saying it this way is what leads to some of the confusion. The truth is, whether you use ‘a’ or ‘an’ has nothing to do with how a word is written or spelled. The difference is entirely for spoken English.

Everyone knows the five and a half vowels (a, e, i, o, u, and sometimes y), but how many people are actually taught what makes a vowel a vowel? The difference between a vowel and a consonant is in what you do with your mouth while you pronounce them.

Consonants are closed sounds. While pronouncing a consonant your mouth closes in one way or another, either by touching your lips together or pressing your tongue against the roof of your mouth. In contrast, while pronouncing vowels you keep everything open.

This difference is actually why consonants and vowels combine so well to form syllables, whereas several consonants in a row are hard to pronounce. It’s also why vowels tend to merge together and change their pronunciation when placed side by side.

For most letters you can only say them one way. No matter how it’s stressed you can’t pronounce an ‘a’ without keeping your mouth open and you can’t pronounce a ‘b’ without closing it.

Y is the exception. Sometimes you pronounce ‘y’ by closing your mouth and then opening it, such as in the words yonder or yodel. In this case it’s a consonant. But other times, such as in the word why, you keep your mouth open, making the ‘y’ a vowel. This is why we say that y is only sometimes a vowel.

So the rule ‘a’ if consonant, ‘an’ if vowel, applies only to the sound it makes. If it sounds like it starts with a consonant, whether or not it does when you write it out, you put an ‘a’ in front of it. Two examples of this are “a unit” and “a eukaryotic cell”. Both of these words sound like they begin with a consonant ‘y’, and so they get ‘a’.

Similarly, if it sounds like it starts with a vowel it gets ‘an’. An heir, or an hour are good examples of this, since in both cases the ‘h’ is silent and thus, when spoken, they begin with vowels.

Again, the reason for this rule is to make spoken English clearer and more fluid. Multiple consonants in a row sound slow and sloppy, which is why “an banana” just sounds wrong. Multiple vowels in a row merge together, which is why “a apple” just turns into “apple” with a long ‘a’ in front. The ‘n’ was added to the end in order to keep space between the two vowel sounds, to make it clear where one word ends and the other begins.

What really gets me are the hypercorrections people make, such as putting ‘an’ in front of every word that begins with an ‘h’. This is why you’ll have people talking about “an historic event.” These hypercorrections stem from people knowing the rules but not really understanding why they exist, which is why I went into more detail than you’d ever wanted to know about vowels and consonants.

Hopefully that cleared somethings up for people. If not, at least it let me rant about something that had been bothering me lately. Until next time,