Word Stress and Suffixes 3

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
stressed vowel:         /i:/               /e/

de’rive – de ‘rivative

stressed vowel:    /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 – col'lision /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? Identify S (Same) or D (Different).

EXAMPLES:
familiarise (S) (fa’miliarise – fa’miliar) –  cancellation (D) (cancel’lation – ‘cancel)

intervention (intervene)  
security (secure)  
advantageous (advantage)  
Canadian (Canada)  
consumption (consume)
maturity (mature)  
stupidity (stupid)  
application (apply)  
sanity (sanity)  
normality (normal)
delivery (deliver)  
precision (precise)  
preference (prefer)  
sincerity (sincere)  
diversion (diverse)

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.

Exercise 4
Match the words from below to the correct column in the table 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