Phonemes
by
Dr. Brian M. Sietsema
associate pronouncer, Scripps National Spelling Bee
Phonemes
are often indicated in a special way, using slant marks and letters from different
alphabets. For example, the phoneme /t/ expresses the idea of the /t/ sound of
English in the words toot, stoop, later, and hit
(even though there are slight differences in the way your mouth produces the
/t/ among these words).
In
purely physical terms, the sounds spelled with the bolded t in each of
those words are each a different sound—or phone, to use the precise
linguistic label. The t at the beginning of toot is produced with
a significant puff of air, unlike the t of stoop. You can convince
yourself of this difference by draping a tissue in front of your mouth as you
pronounce the two words. The t of stoop is hardly distinguishable
from a d; at normal rates of speaking, almost no one would notice if you
were saying "sdoop" rather than stoop.
The
t in later is a kind of consonant that linguists call a "flap"
or a "tap": it is formed by the tip of the tongue giving a swift tap
on the roof of the mouth. This t is the same as the sound of the d
in lader.
At
normal rates of speaking in most dialects of English, the t in hit
is completely different from the rest. Whereas the others are formed somewhere
near the front of the mouth with the tip of the tongue involved, this t
in a phrase like "hit my hand" is formed by a closure back in the throat, with
no involvement of the tongue tip. Linguists call this kind of consonantal sound
a "glottal stop."
Each
of these phones is mechanically and acoustically a different sound: That is, they
are formed in different ways by the vocal organs in the mouth and throat, and
they produce sound waves that are different from one another. While each of these
sounds is spelled with the letter t, linguists would use a different character
to indicate each phone: [th] for toot, [t] for stoop,
[
] for later, and [
]
for hit. (Notice that phones are enclosed in square brackets, but phonemes
appear within slashes.)
As
speakers of English, we regard these different phones as being really just the
expression of a single category of sound, the English phoneme /t/. In our language,
therefore, [th], [t], [],
and [] are all allophones of
the phoneme /t/.
Speakers
of other languages, however, may regard these phones as being distinct kinds of
sound which are therefore to be spelled with different letters. Speakers of Hindi,
for example, hear a clear distinction between [th] and [t], and for
them this difference makes for a difference in meaning. For them, these two phones
belong to two different phonemes, /th/ and /t/. Speakers of Arabic,
on the other hand, perceive the phones [p] and [b] as being essentially one and
the same kind of sound—allophones of a single phoneme /p/; in English we
regard [p] and [b] as expressions of two distinct phonemes /p/ and /b/ that consequently
make for a difference in meaning, as in pat and bat.
A
familiar example of how phones are perceived differently in different languages
comes from comparing English and Spanish. In English, den and then
begin with two different sounds, [d] and [ð], which are regarded as two distinct
phonemes. In Spanish, however, these two sounds are both perceived as allophones
of the Spanish phoneme /d/. These allophones occur in different phonetic contexts:
[d] is found at the beginning of a word, but [ð] after a vowel, as
in the phrase de nada, which to English speakers sounds like "day nah-thah."
In languages
generally, the allophones of a single phoneme occur in complementary distribution.
That is, each phone shows up only in certain contexts—such as at the beginning
or end of a word, between vowels, in a stressed, or unstressed syllable, before
a nasal consonant, etc. No two allophones will show up in the same phonetic environment.
