Vowel sound duration depends on many things.
Hi again, and welcome back to Seattle Learning Academy's American English pronunciation podcast. My name is Mandy, and this is our 158th episode.
This podcast is going to cover some advanced pronunciation topics, so I would advise you to go to www.pronuncian.com/podcast and click episode 158 to read the transcript for this show along with listening to it. Reading along will help you to comprehend the lessons in today's show.
I've spoken quite a few times about voiced and unvoiced consonant sounds before, but I haven't spoken very much about the changes in the vowel sounds that come before voiced and unvoiced consonant sounds.
Before I begin, let me say again that the terms "long" vowel and "short" vowel are common names for vowel sounds in American English. As tempting as it is to think that a long a and a short a are the same sound except for how long we say the sound, that's not how it works. The term long a represents the sound (long a) as in the word cake. The term short a represents the sound (short a) as in the word cat. The sounds (long a) and (short a) are actually about the same duration if everything else is equal. What do I mean, though, when I say "if everything else is equal"?
Well, there are a few different things that change the duration of a vowel sound in a word. First, of course, there is syllable stress. Vowel sounds in a primarily stressed syllable are going to have a longer duration than vowel sounds in secondarily stressed or unstressed syllables. For example, take the word timid, t-i-m-i-d. (The word timid means to be shy.) Timid is a two-syllable word with the first syllable stressed. Both syllables have a short i sound, but the short i of the first syllable has a longer duration that the short i sound of the second syllable. Listen again: timid, timid.
Also, a vowel sound in a word that is stressed in a sentence has a longer duration than the same vowel sound in an unstressed word. If I use the word timid in two different sentences, once as a stressed word and once with the word not stressed, you should be able to hear the difference.
First, here it is stressed: Chloe is so timid.
And here it is in a less stressed position: Chloe is such a timid kitten.
In the first sentence, the first short i of the word timid takes more time than in the second sentence because the whole word is stressed more in the first sentence. In the second sentence, the word kitten has a longer duration short i sound. Listen to both sentences again:
Chloe is so timid.
Chloe is such a timid kitten.
So, remember for the rest of this podcast that vowel duration is relative to a number of different circumstances: first, syllable stress; second, word stress in a sentence; and third, what sound follows the vowel sound in a word. Yes, a vowel sound will change duration based on the sound following it being voiced or not.
Let's do another little review of concepts. In English, we have sixteen consonant sounds that occur in voiced/unvoiced pairs. A voiced consonant sound includes vocal cord vibration during its production, and an unvoiced sound does not. To feel the difference between a voiced and unvoiced sound, let's do a little experiment.
Place two fingers on the front of your throat. Yes, you have to actually do this in order to understand what I'm talking about. So, put two fingers on front of your throat. Now say the b sound (b sound, b sound). Now say the p sound (p sound, p sound). Can you feel the difference on your fingers? You should feel a vibration during the voiced b sound, but not feel it during the unvoiced p sound. If you feel it for both, you may be adding a vowel sound to the p sound. You should be saying (p sound), and not (p sound+vowel sound). If you're saying (p sound plus vowel sound), you'll feel the vibration of the (vowel sound), which is not actually part of the p sound.
Let's do the experiment again. With your fingers against the front of your throat, say the b sound (b sound) and the p sound (p sound). At it's very simplest, that is the difference between a voiced and unvoiced sound. A voiced sound vibrates in your throat.
When I say "voiced/unvoiced pair," I'm talking about two sounds that use the same shape of the vocal tract. Since the b sound and p sound are created using the lips in the same way, they are a voiced/unvoiced pair. Another example is the z sound and s sound. The z sound is voiced, the s sound is not; the shape of the tongue for both sounds is essentially the same.
I also use the term "minimal pair" a lot in these podcasts. A minimal pair is a pair of words that are the same except for one sound. For instance, the words robe and rope are a minimal pair. The words are the same except that the word robe ends in a b sound and the word rope ends in a p sound: robe, rope. Similarly, the words buzz and bus are a z sound/s sound minimal pair.
If you listen carefully to the pairs (robe/rope and buzz/bus), you'll notice that the vowel sound in the words changes slightly in duration. The vowel sounds in the words robe and buzz take more time than the vowel sounds in the words rope and bus. This tiny and odd little vowel feature is actually an important clue as to which consonant sound was said in a word.
Listen to the pairs again:
As I said in the beginning, we have 8 voiced/unvoiced pairs of sounds in English. Two pairs of these sounds, the voiced and unvoiced th sounds and the zh sound and sh sound do not have any minimal pairs to use for comparison. The other 6 pairs, however, do have nice words that we can use for hearing and practicing this difference in pronunciation.
First, let's practice the three pairs of stop sounds: the b sound/p sound, d sound/t sound, and g sound/k sound. I'll say a pair of words for each pair of sounds. I'll leave time for you to repeat after me:
b sound/p sound: robe, rope
d sound/t sound: bad, bat
g sound/k sound: pig, pick
And here's a pair for our affricate sounds, the j sound and ch sound:
And finally here are the two pairs of fricative sounds that have words that we can use:
v sound/f sound: save, safe
z sound/s sound: eyes, ice
I'll say all of those pairs again for you to repeat after me:
Since we're talking about so many minimal pairs today, I should mention our minimal pairs collection on Pronuncian.com. We've gotten through creating lists for almost all of the combinations of vowel sounds and consonant sounds, and they're free for you to access. Just go to www.pronuncian.com and click the "Minimal Pairs" icon on the homepage, then click whatever pair you want to practice. That's just one little bit of the free material we have on Pronuncian. We also have helpful books you can buy to help you study even more. The information I covered today about the differences in vowel duration before voiced and unvoiced sounds is covered in our most popular book, "Pronunciation Pages 2: Sounds of American English." You can purchase a downloadable version and download it directly to your computer, along with MP3 audio files, or you can purchase the physical version of the book and have it shipped to you along with a CD version of the MP3 files. Of course, your purchases help support all the free content, like the minimal pairs tables, that we offer on the website.
That's all for today everyone. This has been a Seattle Learning Academy digital publication. SLA is where the world comes to learn.
Thanks for listening, and good luck!