Stress is a main feature of supra-segmental (or: prosodic) phonology. It is closely linked to rhythm and intonation, two other characteristics of prosody. In a phonetic sense, stress is part of articulatory phonetics and is produced by alternation of breath pressure, pitch, duration and sound quality (the auditory counterpart of stress is prominence). There are several reasons why we use stress in a language. In English the main purpose is to place a prominence on certain words, to structure an utterance and last but not least, stress can also have a contrastive function as in invalid (‘invalid – noun, in’valid – adjective -> Exercise: Verb, Noun, Adjective? ). Of course from an auditory point of view, stress also makes it easier to listen and to understand. In the English language there are three different levels of stress that can be put on a syllable.
- Primary stress: Primary stress usually is very strong and can occur in every word, very striking in monosyllabic words, e.g. ‘window, sta’tistics.
- Secondary stress: In polysyllabic words sometimes a secondary stress can be found, which is placed on the second strongest stressed syllable (mostly the first) within the word, e.g. ,inter’ference.
- Unstressed syllables: The third and last category (at least the last category important to us) is the unstressed syllable, e.g. ,inter’ference.
Concerning word stress, there are no really fixed rules of where to put the stress in a word in English (it is a free-stress language). However stress is closely linked to the field of syllables and vowels and sometimes it is possible to predict the stress within a word because of these features. The schwa-sound for example never occurs in stressed syllables. Furthermore weak syllables are always unstressed, while unstressed syllables can be strong and weak.
Another interesting phenomenon is the reduction of (full or strong) vowels. Here a shift in word class is brought about by a shift in stress which leads to a reduction of the vowel. Take the word subject for instance. It is stressed on the first syllable when we speak of the noun: ‘subject ['sʌbdʒekt] and stressed on the second syllable when we speak of the verb: sub'ject [səb'dʒekt]. As you can see in this example, the ʌ got reduced to a schwa because of or rather in order to show the shift in word class and meaning.
There are also some syllables that indicate the word stress, the suffix -ity for example leads to a stress on the antepenultimate syllable, e.g. pro’fanity. Finally there are three general stress rules:
- 1. Monosyllabic words: These words are always stressed (of course looking at isolated words, not words within an utterance).
- 2. Polysyllabic words:
Noun rule: stress the penultimate syllable if heavy. If the penultimate syllable is light, stress the antepenult:
Verb rule: stress the final syllable if heavy. If the final syllable is light, stress the penultimate syllable:
o'bese, a'ccuse; 'meddle
- 3. Compounds: Compounds, that means, words, that are composed of two independent words are stressed on the first syllable: