4.5.2 Stress and rhythm
The phenomenon of stress is difficult to define acoustically. Functionally, it serves to
emphasize something against the background of its environment. This can take place in
the form of a change in loudness, a change in pitch, or a change in duration. Usually,
two or three, sometimes four, distinct levels of stress are recognized, namely, primary
<>, secondary <>, tertiary (not used in the following) and unstressed (unmarked). Stress
has an immediate influence on how a phoneme is realized inasmuch as unstressed sylla-
bles tend to have vowels with a schwa. Note the initial vowel of atom, which is (stressed)
/
/, while the unstressed first syllable of atomic is /ə/. The weak stress of some sylla-
bles can lead to an identical realization of otherwise differing words, e.g. drive and derive
may both be /dra
v/. Naturally, these words are hardly likely to occur in contexts in which
they might be confused, and even if they did, speakers could easily remedy the possible
confusion by using a more careful pronunciation of derive, /d
ərɑv/.
Aside from its influence on the realization of phonemes, stress has two further
important functions. For one thing it differentiates lexical pairs such as Main Street and
main street or pass on (‘to judge’ as in we didn’t feel capable of passing on her qual-
ifications) and pass on (‘hand to the next person’).
Secondly, it marks (in connection with intonation) the word which carries the syntactic
or sentence stress. In the careful style of spoken prose, e.g. a speech read at a meeting or
the news read on radio or television, this is usually the last lexical word (noun, full verb,
adjective or adverb) in a clause. Most frequently the rheme (see 5.4.4), or that part of
the sentence which contains new information, carries the stress. If a different word, for
example, a function word such as an article, a pronoun, an auxiliary verb, a preposition or
a lexical word besides the final one is to be stressed, this will be a case of contrastive
stress. This means that the item which carries the stress is consciously emphasized in oppo-
sition to what might otherwise be the case, e.g. Jerry doesn’t eat pickled herring (even
though Diane does). One author calls this second function of stress, in which a particular
word which contains new information is emphasized, tonicity (Halliday 1970: 40ff.).
The connection between rhythm and stress is an important feature of English. All
lexical words carry a primary or secondary stress. The pattern which arises from this
series of stresses provides the skeleton of English rhythm, for all the remaining syllables
are (relatively) unstressed. English (like German) is, for this reason, referred to as a stress-
timed language as compared to a syllable-timed language (such as Spanish). It is often
suggested that English has largely even rhythm, or isochrony, with each of the stresses
occurring at equal time intervals.
Most lexical words contain only one stressed syllable. The remaining, unstressed sylla-
bles tend to be reduced to a schwa. This makes for notorious spelling problems for native
speakers of English, who have difficulty remembering how to spell these unstressed
vowels (for example, *<attendence> or <attendance>.) Yet, because there can be shifts
in the syllable which carries the stress, the full value of many of these unstressed vowels
must be restored, for example Jefferson with final /-s
ən/ becomes Jeffersonian with final
/-so
υniən/, while Dickens, also with a final schwa /-ənz/ becomes Dickensian with final
/-enzi
ən/. In the following examples some of the endings which cause a change in stress
are listed. We begin, however, with examples of derivational suffixes which cause no
change and then go on to some which do cause a change as well as a few which some-
times do and sometimes do not.
86 ENGLISH AS A LINGUISTIC SYSTEM