Delahunty and Garvey
- All vowels can occur in syllables (see below) that end in at least one
consonant (closed syllables); [i], [e], [u], [o], [O], and [A] can occur as
the final sound in a syllable (open syllables). - Muscle tension: [i], [e], [u], [o], [O], and [A] are produced with great-
er muscle tension in the articulators than [I], [E], [], [U], and [V]
are. The former are tense vowels; the latter are lax. The greater tension
in [i], [e], [u], [o], [O], and [A] may explain why they are longer and
more peripheral, i.e., closer to the boundary of the mouth, than the
other vowels.
Even though there are several differences separating these two sets of
vowels, we will refer to them as tense and lax vowels. Table 5 lists all of
them:
tense lax
beat, bee [i] hit [I]
boot, boo [u] hood [U]
bait, bay [e] head [E]
boat, beau [o] hat []
bought, paw [O] hut [V]
pot, spa [A]
table 5: tense and lax vowels
You may have noticed that all of the example words we have used to exem-
plify the vowels we have distinguished consist of a single syllable. This is
because vowels in multi-syllabic words can differ from those in monosyl-
lables, and we wanted to compare vowels in similar contexts. We have now
distinguished the following vowels:
front central back
i u
I U
e o
E V O
{ A
table 6: english vowels in monosyllabic words
Not all American English speakers distinguish [O] and [A] in all contexts.