Strong and Weak Forms in English

Content words (both monosyllables and polysyllables) generally retain their full vowels in connected speech and hence have a level of prominence above that of syllables with reduced vowels, even when no pitch prominence is associated with them. But many function words (pronouns, prepositions, auxiliary verbs, conjunctions, articles) have different patterns according to whether they are unaccented (as is usual) or accented (in special situations or when said in isolation). Compared with the accented (STRONG) forms, the unaccented WEAK forms of these words show reductions of the length of sounds, centralisation of vowels towards /ə,ɪ,ʊ/ and the elision of vowels and consonants.