Among the many differences between British and American English is the way that vowels are treated in unstressed syllables. For the most part, British English tends to pronounce them with schwa, so that the final vowel in Pentagon and Amazon, which has a relatively full vowel in American speech, has a reduced vowel in British. Occasionally, the results are inverted, so that the final syllable of Maryland and partisan in British speech has the full vowel, whereas a schwa is the norm in American.

The occurrence of a reduced vowel in unstressed position (or in syllables with potentially secondary stress) is to be interpreted as a sign that the word is being interpreted as a unified whole, with a constituent structure. Maryland pronounced by a speaker of American English is thus construed as having no segment structure phonetically, whereas in British speech the maintenance of [a] and secondary stress is a sign that speakers are interpreting the word has having two constituents, Mary– plus –land.

This sort of (tacit) construal of a word’s constituent structure has different phonetic outcomes in the speech of newer vs. older generations of American speakers when it comes to items that contain final morphemes like {ent} in student and president, with younger speakers coming increasingly to pronounce them with a full vowel rather than the traditional schwa. This secondary stress in the newer variant seems to be occasioned by the reconstrual of these words as containing a suffix, since the stems (stud– and presid-) also occur elsewhere in verbs.