Some words don’t change their stress pattern when a suffix is added to the root word, but do change the pronunciation of the vowel in the main stressed syllable. Compare:
| ex ‘treme – ex ‘tremity | /i:/ /e/ |
| de’rive – de ‘rivative | /aɪ/ /ɪ/ |
The following table shows a number of possible vowel changes. The main stressed syllable and the pronunciation of the vowel in this syllable are shown:
=> /ɪ/
/aɪ/’bible-‘biblical/ɪ/
/aɪ/ type – ‘typical /ɪ/
/aɪ/ wise – ‘wisdom /ɪ/
=>/ɒ/
/ɔː/ ex’plore – ex’ploratory /ɒ/
/əʊ/ know – ‘knowledge /ɒ/
=>/æ/
/eɪ/ ‘nation – ‘national /æ/
/eɪ/ de’fame – de’famatory /æ/
/eɪ/ sane – ‘sanity /æ/
/eə/ com’pare – com’parative /æ/
/eə/ de’clare – de’clarative /æ/
/ɑ:/ ‘drama – ‘dramatise/æ/
=>/e/
/i:/ com’pete – com’petitive /e/
/i:/ inter’vene – inter’vention /e/
/i:/ ob’scene – ob’scenity /e/
=>/ʌ/
/u:/ as’sume – as’sumption /ʌ/
/u:/ pre’sume – pre’sumption /ʌ/
In some words, as well as a change in the pronunciation of the vowel in the stressed syllable, there is also a change in the pronunciation of the consonant(s) that follow it.
/aɪt/ ig’nite – ig’nition /ɪʃ/
/aɪn/ sign – ‘signature /ɪgn/
/u:s/ pro’duce – pro’duction, pro’ductive /ʌk/
/u:s/intro’duce – intro’duction, intro’ductory /ʌk/
In other words like this, there is a change in the pronunciation of the vowel in the stressed syllable and also the spelling of either this vowel and/or the consonant(s) that follow it:
/aɪd/ col’lide – collision /ɪʒ/
/aɪd/ di’vide – di’vision /ɪʒ/
/aɪd/ pro’vide – pro’vision /ɪʒ/
/aɪb/ de’scribe – de’scription, de’scriptive /ɪp/
/aɪb/ pre’scribe – pre’scription, pre’scriptive /ɪp/
/aɪb/ sub’scribe – sub’scription /ɪp/
/i:v/ de’ceive – de’ception, de’ceptive /ep/
/i:/re’peat- re’petitive /e/
/a:/ex’ample – ex’emplary /e/
/e/ re’tain – re’tention /e/
/eɪ/ ex’plain – ex’planatory /æ/
/aɪ/ ap’ply – ap’plicable /ɪ/
Words that do change their stress pattern when a suffix is added to the root also commonly change their pronunciation in one or more syllable:
pro ‘nounce – pronunci ‘ation
/ə/ /aʊ/ /ə/ /ʌ/
pre’fer – ‘preferable
/ɪ/ /3:/ /e/ /ə/
Exercises
Exercise 1
Which of these words have main stress on the same syllable as their root word? Write S (Same) or D (Different).
EXAMPLES familiarise (S) (fa’miliarise – fa’miliar) – cancellation (D) (cancel’lation – ‘cancel)
intervention ( ) security ( ) advantageous ( ) Canadian ( ) consumption ( )
maturity ( ) stupidity ( ) application ( ) sanity ( ) normality ( )
delivery ( ) precision ( ) preference ( ) sincerity ( ) diversion ( )
Now listen and check your answers.
(Australia) familiarise (S) (fa’miliarise – fa’miliar) – cancellation (D) (cancel’lation – ‘cancel)
intervention = S (inter’vene)
se’curity = S (se’cure)
advantageous = D (ad’vantage)
Ca’nadian = D (‘Canada)
con’sumption = S (con’sume)
ma’turity = S (ma’ture)
stu’pidity = D (‘stupid)
application = D (a’pply)
‘sanity = S (sane)
nor’mality = D (‘normal)
de’livery = S (de’liver)
pre’cision = S (pre’cise)
‘preference = D (pre’fer)
sin’cerity = S (sin’cere)
di’version = S (di’vert)
Exercise 2
Look again at the words in Exercise 1 with main stress on the same syllable as their root.
Underline the ones which have a different vowel sound in the main stressed syllable from that in the main stressed syllable in their root.
EXAMPLE intervention (intervention /e/ – inter’vene /i:/)
Now listen again to the words in Exercise 2 and check your answers.
The words with a different vowel sound from their root are:
intervention /e/ (intervene /i:/)
consumption /ʌ/ (consume /u:/)
sanity /æ/ (sane /eɪ/)
precision /ɪ/ (precise /aɪ/)
sincerity /e/ (sincere /ɪə/)
The words with the same vowel sound as their root are:
familiarise /ɪ/ (familiar /ɪ/)
security /ʊə/ (secure /ʊə/)
maturity /ʊə/ (mature /ʊə/)
delivery /ɪ/ (deliver /ɪ/)
diversion /3:/ (divert /3:/)
Exercise 3
Complete each pair of sentences using the pairs of words below.
collide-collision / compete-competitive / divide-division
example-exemplary / nation-national / subscribe subscription
EXAMPLE
a It costs £10 a year to __subscribe__ to the sports centre.
b I’ve taken out an annual __subscription__ to the magazine.
1 a We’ll ____ the money between us.
b Brighton football club was promoted to the first ____ .
2 a It’s difficult to stay ____ in business.
b He was much faster and I couldn’t ____ with him.
3 a Rod broke his leg in the ____ .
b They say the comet is going to ____ with Saturn.
4 a She set a good ____ to her younger sister.
b Their behaviour was ____ .
5 a The first of May is a ____ holiday.
b Practically the whole ____ watched the eclipse.
Now listen and check your answers. Then read the sentences aloud.
1 a divide b division
2 a competitive b compete
3 a collision b collide
4 a example b exemplary
5 a national b nation
Exercise 4
Write the words from the box in the correct column according to the vowel sound in the main stressed syllable of their root word. There are three words in each column.
commercial applicant speciality financial symbolic
evolution accidental historic decision demonstration
influential modernity calculation magnetic medicinal
| Vowel sound in main stressed syllable of root |
/ɒ/ (as in stop) | /ɪ/ (as in sit) | /aɪ/ (as in drive) | /æ/ (as in black) | /e/ (as in pen) |
| *commercial evolution modernity |
*Their roots all have /ɒ/ in their main stressed syllable: commerce, evolve, modern
| Vowel sound in main stressed syllable of root |
/ɒ/ (as in stop) | /ɪ/ (as in sit) | /aɪ/ (as in drive) | /æ/ (as in black) | /e/ (as in pen) |
| commercial (commerce) evolution (evolve) modernity (modern) |
symbolic (symbol) historic (history) influential (influence) |
applicant (apply) financial (finance) decision (decide) |
accidental (accident) calculation (calculate) magnetic (magnet) |
speciality (special) demonstration (demonstrate) medicinal (medicine |