Occurrence, to be accounted for, entity, predetermine, assumption, isochrony, underlying tendency, simultaneously, juxtaposed.
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Regularity of occurrence of stressed syllables in English is closely related to another important feature of English rhythm: alternation of stressed and unstressed syllables. This tendency may be accounted for by several reasons and, first of all, by a high frequency of monosyllabic notional words (disposed to be stressed in an utterance) and intervening function-words (usually unstressed). A sequence of disyllabic words which typically have one stress presents a similar pattern of alternating stressed and unstressed syllables even though there may be a number of form-words between the notional ones. It must be understood that the alternation of stressed and unstressed syllables is but rarely of an “ideal” pattern, such as in the following utterances, e.g.:
I 'can't beˈlieve my ‵eyes. He 'never 'comes a‵lone.
The ratio of stressed and unstressed syllables may be one to two, one to three, or even more, e.g.:
They are 'leaving to'morrow by ‵air.
The ˈbus is more conˈvenient than the ‵tram.
Moreover, in the majority of cases the number of unstressed syllables between the stressed ones varies within an utterance, i.e. the rhythmic groups have uneven numbers of syllables, e.g.:
Will 'someone 'meet you at the ‚station?
The tendency to alternate stressed and unstressed syllables thus appears to merely reflect the peculiarity of the composition of an English utterance and its utterance-stress. However, this tendency becomes active, i.e. capable of introducing certain modifications in the accentual structure, when an utterance consists exclusively of monosyllabic notional words, e.g.:
'Come next ‵week. ˈNow turn ‵left.
In such cases stressing all the consecutive words is generally avoided, although there may be instances of juxtaposed stress if the meaning requires it, e.g.:
'Most 'boys 'like ‵dogs.
The same tendency to avoid stressing adjacent words is observed even when these words are not monosyllables. We may conclude, therefore, that the above-mentioned peculiarity is not restricted to the alternation of stressed and unstressed syllables but involves alternating stressed and unstressed (prominent and non-prominent) words as well. As a result, the “normal” stressing of words in an utterance can be modified: words entitled to become prominent due to the their content nature are “deprived” of prominence in an utterance if both the immediately following and immediately preceding words are stressed, e.g.:
She is a 'very good ‵actress. but: She is a 'good ‵actress.
This phenomenon is known as the influence of rhythm on utterance-stress. It must be emphasized, however, that such modifications as those illustrated in the above examples should not interfere with the communicative meaning of an utterance; in other words, the decisive factor for utterance-stress is the semantic weight of a word in the given context.
The tendency to alternate strong and weak syllables accounts for making two syllables prominent in many English polysyllabic words, e.g.:
e'xami‵nation / 'abso‵lutely / con'side‵ration
In connected speech, however, such words may lose one of the stresses or, at any rate one of the stresses is somewhat suppressed, i.e. made partial, e.g.:
The 'girl looked 'absolutely ‵lovely.
They've been 'talking about the e'xami‵nations.
The omission of one of the stresses is more typical of double-stressed words with a second stress having a semantic function, e.g. weekend, unknown, well-known, etc., whereas polysyllabic derivative words, like examination, conversation are more stable in the accentual pattern, particularly, because initially the double-stressed pattern of such words is already the result of the rhyhmic tendency.