English is traditionally described as having “long” and “short” vowels. Despite this terminology, the distinction has nothing to do with length. In fact, a long vowel is one where the pronunciation matches the name of the letter. For example, the “a” in “made” is a long-A, because it is pronounced like the name of the letter A. The “o” in “throne” is another example of a long vowel, this time a long-O. Short vowels, on the other hand, have unpredictable pronunciations. Despite the name, they are not short versions of the long vowels. They are actually completely different vowels with no relation at all to their long counterparts. The “a” in “mad”, or the “o” in “done”, are considered short vowels because their pronunciations do not match the names of the letters.
This is a system of vowel classification that just doesn’t work. The fundamental problem is that it is based on the letters of the alphabet. Since there are only 5 vowel letters, you can describe at most 10 possible vowels. However, all English dialects have more than 10 vowel sounds, which means that the long/short classification is doomed to failure. There are always going to be some vowel sounds that cannot be represented, because there aren’t enough symbols to keep them all distinct.
For example, consider the “a” in “lack” and the “a” in “father”. Neither of them is like the name of the letter A, nor are they like the name of any other vowel letter, so they would both have to be classified as short-A. This is clearly wrong. These are distinct vowels, and it is wrong to lump them together as examples of the same category.
To add to the confusion, the “a” in “father” represents exactly the same sound as the the “o” in “lock”. Is this vowel in “lock” a short-A, because it sounds like another sound called short-A? Or is it a short-O because it spelled with an “o”? Neither option is desirable. Another example: what do we do with the vowel in “food” and the vowel in “rude”? It’s the same vowel in both cases, but spelled with different letters. Is this sound a short-O in “food” and a short-U in “rude”? Why call it a different name when its the same thing? (And why would a short-O be spelled with a doubled letter?) Speaking of “u”, the long-U sound isn’t even a vowel! The name of the letter U is a a full syllable; it is a sequence of a consonant [j] and a vowel [u].
You might wonder why the letter Y is not part of this categorization. That would allow for 2 more vowels into the sytem, for a total of 12. However, there doesn’t seem to be any long-Y sound. The letter Y never represents a sound like its name [wai]. (Except, maybe, in the word “why”.) Sometimes, Y represents a consonant, as in “yellow” or “Mayan”. Other times, it represents a vowel, and there are at least three different vowels it can be: “thyme”, “rythm” and “baby” all have different “y” sounds. You might expect these could be called short-Y sounds, but I that doesn’t seem to be very common. Instead, it seems like people refer to these as short-I sounds, which makes no sense to me at all.
A quick lesson in phonetics
To understand the vowels of English, you can’t think of them as letters. You have to think of them as speech sounds. Sounds and letters are completely different things, and this really matters. Talking about sounds gives us the proper level of description. A quick introduction to phonetics will help clarify thing. I should make a note here: phonetic symbols are represented using square brackets, like [s]. If I need to refer to spelling letters, I’ll put them in quotes like this “s”. So the letter “s” can represent the sound [s], as in “sap” or the sound [z] as in “miser”.
To produce speech, air is pushed out of your lungs. It travels past the vocal folds in your throat, possibly causing them to vibrate and make noise. (Here’s a video the vocal folds of four singers. It’s probably the weirdest thing you’ll watch today.) Finally, the air escapes your body, either through your nose, your mouth, or both. If air is trapped or forced around constrictions during this journey from lungs to outside world, then the sound is considered a consonant. If the air flows more or less freely, then the sound is considered a vowel.
For example, to make the sound [s], your tongue tip has to raise up behind your top teeth so that air is forced through a narrow constriction (which is what gives [s] its characterisic hissing sound). Therefore, [s] is a consonant. On the other hand, the sound [a], the first sound in the word “on”, is made without any obstruction in your mouth at all. Therefore, [a] is a vowel.
What makes consonants different from each other is the location of the obstruction, and what the air has to do to get around it. If you close your lips and re-direct air through your nose, you can get an [m] sound. If you press your lower lip to your upper teeth and blow air through quickly you’ll get an [f] or [v].
Vowels don’t have any obstructions, by definition, so what makes vowels distinct from each other is the size and the dimensions of the space that air flows through. One way you can control the size of this space by moving your jaw up and down. The word “see-saw” is a good example of this. Say that a few times. For “see”, your jaw is raised, and for “saw” you lower the jaw and open your mouth wider.
What you do with your tongue also changes the dimensions of your mouth, and therefore changes the quality of the vowel that you produce. The vowel in “phone” has a higher tongue position than the vowel in “fawn”. The vowel in “boat” has the tongue further back in the mouth than the vowel in “bet”. These changes in position are actually a little tricky to feel without some practice. Linguists normally study the phonetics of vowels by using ultrasound machines (and X-rays way back in the day when people thought that was safe). There’s a really nice website where you can click on a phonetic symbol to watch an ultrasound video of someone’s tongue producing that sound (consonants here, vowels here).
In linguistics, vowels have two major characteristics: their “height” and their “backness”. These terms refer to the position of the tongue when articulating the vowels. High vowels are produced with a tongue closer to the roof of the mouth, while mid and low vowels are produced with lower tongue positions. Back vowels involve a retracted tongue, while central and front vowel have a tongue tip closer to the teeth. There are many other properties of vowels that may be relevant in a language, such as nasality (whether air flows through the nose or not) and roundedness (whether the lips are rounded or not). I won’t discuss vowel phonetics in detail here, but if you want to read more about it I have a post over here.
This is short take-away message: Classifying vowels on the basis of their phonetics ensures that we can tell all of the vowels apart. In traditional terms, the (distinct) vowels “father” and “lack” are both short-A. In phonetic terms, the vowel in “father” is a low back vowel, while the vowel in “lack” is a low front vowel. In other words, they differ in their “backness”. This is an improvement on the traditional terms which would classify them as the same vowel.
I think it would make far more sense to get rid of the traditional notions of “short” and “long” and start teaching people something useful. A phonetics-based approach teaches students about how pronuncation actually works, and it’s a model that you can use for literally any language on Earth. All humans have basically the same vocal tract anatomy, so the phonetic terms you learn for English will, more or less, work for any other language you might study later. The traditional terms “long” and “short” will be useless for other languages.
It’s not even that hard to remember terms like “high/mid/low” and “front/centre/back”, because these are terms that actually refer to something real. In contrast, the traditional terms “long” and “short” are totally arbitrary labels that students simply memorize. There is no additional insight gained into how language works. In fact the traditional terminology obfuscates things by labelling distinct phonetic vowels as the same (“lack” and “father” both have short-A).
Are “short” and “long” useless labels?
I should say that there is nothing wrong with the idea of “long” and “short” vowels, in general. In many human languages, the length of a vowel, meaning the duration in milliseconds, is something that actually matters. For example, Thai has both long and short vowels. The word [cip], with a short vowel, means “to sip” while [ci:p], with long vowel, means “to flirt” (the common phonetic notation for a long vowel is to add a colon after it). The word [het], with a short vowel, means “mushroom” while [he:t], with a long vowel, means “cause”. In one experiment, a native speaker of Thai was recorded producing pairs of words with long/short vowels, and the length of his vowels was measured. The short [i] in [cip] lasted 30-35 milliseconds. The long [i:] in [ci:p] lasted more than 100ms. That’s enough of a difference that I suspect even a non-native speaker would notice it. I should add that length isn’t everything. Long vowels and short vowels may also differ in other phonetic properties as well.
While we’re at it, it’s not just vowels that can be long. Consonants can be long too, but in this case they are often referred to as “geminate” consonants. For example, in Norwegian words can differ by consonant length: sine means “theirs” while sinne means “anger”. Note that a double “n” doesn’t mean that you say two [n] sounds in a row. Rather, you say a single [n] but the pronunciation lasts for a longer period of time.
A return to English vowels
Now here’s the interesting thing: English actually does have short and long vowels, meaning vowels with different physical durations. However, vowel length in English is quite a different phenomenon from Thai. The difference is that the length of a vowel in Thai is completely unpredictable. You can have two words that are exactly identical, except that one of them has a longer vowel (I gave some examples earlier like [het] “mushroom” and [he:t] “cause”). You cannot formulate a general rule for when a vowel will be long in Thai – you just have to memorize vowel length with every word that you learn.
In English, on the other hand, the length of a vowel is completely predictable. If a vowel comes before any of these sounds [p,t,k,f,θ,s,ʃ], then it will be short. Otherwise it will be long. In phonetic terms, vowels are short before voiceless consonants, and long before voiced consonants.
You can do a quick experiment to see this yourself (assuming you are a native speaker of English). Say “ice”. Say “eyes”. Note how the vowel in “ice” is shorter and the one in “eyes” is longer (in non-technical terms, you might say that the vowel in “eyes” is more drawn out). This is because in “ice”, which is phonetically [ais], the vowel is before a voiceless consonant. In “eyes”, phonetically [ai:z], the vowel is before a voiced sound.
Here are some other pairs to consider:
To really get a sense of this, you should literally say these words out loud. Whispering or talking in your head is not the same thing. To get the right phonetic qualities, you need to say these in a normal speaking voice at a normal speaking rate. It can help to put the words in a short sentence so that you get into a natural speaking rhythm, something like “The first word is feet, the second word is feed”. (In real-life phonetics experiments, this is exactly what scientists ask participants to do.) I always tell new students that talking to yourself is considered professional behaviour in linguistics, so don’t be afraid to do it.
Does length matter?
Of course, if you wanted, you could pronounce any English vowel as long or short. It doesn’t really matter, because the distinction in English doesn’t contribute to any difference between words, unlike in Thai. If you pronounce an English vowel that’s normally long as short instead, it won’t change the meaning of the word. If you do this all the time, people may think you have an accent, but they’ll understand what you mean. On the other hand, if you swapped long and short vowels in Thai, you would say some very confusing sentences.
Let’s put this in technical terms: vowel length in Thai is “phonemic”, meaning that it distinguishes words, and in English it is “allophonic”, meaning that it never distinguishes words and is a predictable effect of pronunciation.
The concepts of “phonemic” and “allophonic” apply to all languages. Phonetic terminology too is universal. I think that these are core concepts that should be included in standard English language education. Trying to get people to learn about English with the traditional vowel-length categories is crazy, and it will never work properly. There is a real system to the way that vowels work in English, and it is possible to describe them with sophistication. I think it’s time to abandon the old system of vowel length, and bring in something based on phonetic sciences.