An ELT Glossary : Affix / Affixation

  • Definition : Affixation is the morphological process of adding an affix to the stem of a word (a free morpheme), thus modifying its meaning and/or changing its word class. An affix is a bound morpheme (part of a word with recognisable meaning/use which cannot stand alone) 
  • Examples : a)  "un" as in unhappy : the affix changes the meaning of the free morpheme happy from positive to negative; b)  "ly" as in quickly : the affix changes the form of the free morpheme quick from an adjective to an adverb.
  • As these examples show, in English affixes may occur at the beginning of a word - eg unhappy - in which case they are called prefixes, or at the end - eg quickly - in which case they are called suffixes. In other languages, they may also occur in the middle, in which case they are called infixes (eg in Tagalog the past tense marker is um: sulat = to write , sumulat = I wrote).
  • Affixes may have different variants - or allomorphs. For example, the negative prefix un-, mentioned above has a number of allomorphs: im- as in imprecise, il- as in illogical, ir- as in irrelevant, dis- as in disappointed and others.
  • Some affixes cause spelling changes to the free morpheme. Eg friendly but friendlier; long but length; Spain but Spanish; nine but ninth.

Further reading

The Cambridge Online Grammar : Prefixes and Suffixes
Gairns and Redman, Working with Words, Cambridge

Test Yourself

Look at the following extract from a novel (Camilla Läckberg, The Preacher) : 

Sweat made the sheet stick to her body. Erika tossed and turned in bed, but it was impossible to find a comfortable position. The bright summer night didn't make it any easier to sleep, and for the thousandth time she made a mental note to buy some blackout curtains to hang up, or rather to persuade Patrick to do it.

1. Comment on the form and use of affixes in the underlined words. 

2. What difficulties might each word cause for learners -  including, but not restricted to, problems with the affix? 

Now scroll down for the answers...

Suggested Answers


1.  turned

Affixation : Free morpheme turn (verb) plus regular past tense suffix –ed

Problems :

a. Pronunciation (productive): Ls may pronounce the suffix as it is spelt, producing */tɜ:nɪd/ or  * /tɜ:ned/  rather than /tɜ:nd/

b. Meaning/Use: The verb is part of the binomial expression tossed and turned with the meaning “moved restlessly”. Learners may not recognise this and be puzzled by the inclusion of tossed, or may misremember it and later produce it as turned and tossed.


2. impossible

Affixation: Free morpheme possible (adjective) plus negative prefix  im-


a. Pronunciation (productive): Italian Ls may use the long vowel /i:/ rather than the short /ɪ/ and overstress the final syllable, resulting in */i:mpɒsi:bʊl/ rather than /ɪmpɒsɪbl/

b. Choice of prefix: The negative prefix has a number of allomorphs (Cambridge Dictionary). Some learners may attempt to use the allomorph 'in' (or think that is what they are hearing). They may also try to use one of the other more common possibilities such as  un-.


3. comfortable

Affixation: Free morpheme comfort (noun) plus the adjective suffix -able indicating the concept “fit for” (Merriam-Webster dictionary).


a. Pronunciation (productive): comfortable is stressed on the first syllable and pronounced with reduction of the unstressed vowels - /ˈkʌmfətəbəl/ -  or possible complete elision (omission) of the vowels in the second and fourth syllables - /ˈkʌmftəbl/. Learners may place the stress on the second or third syllables, using the strong form of the vowels and potentially producing  */kʌmfɔ:teɪbel/

b. Spelling : Learners may misspell the suffix as its allomorph –ible, producing *comfortible


4. easier

Affixation: Free morpheme easy (adjective) plus comparative suffix –er. The final “y” of easy changes to “i” as preceded by a consonant.


a. Spelling : Ls who don’t understand the spelling rule may produce “easyer”.

b. Formation of comparative: Two syllable adjectives sometimes take the –er suffix and sometimes “more”. Learners may be confused about which is correct or whether both are possible. The BNC Spoken Corpus (checked on Lextutor) produces 793 examples of easier as opposed to 8 of more easy, showing that while both are used, easier is by far the most frequent. Checking written corpora produced no examples at all of more easy.


5. thousandth

Affixation: Cardinal number (free morpheme) thousand is changed to an ordinal number by the addition of the suffix -th


a. Pronunciation (productive): Many L1 groups have problems with the pronunciation of /θ/ as it occurs in relatively few languages. Here it occurs at both the beginning and end of the word and Ls might replace it with eg /t/ or /s/. The problem would be compounded in the final syllable if they did not realise the /d/ is elided and tried to pronounce /ndθ/ a consonant cluster

b. Spelling – this pronunciation problem might cause the Ls to spell the “th” with “t”. This might be a particular problem for German learners for whom the word is a cognate - tausendste


6. curtains

Affixation: Plural “s” suffix added to countable noun curtain (free morpheme). As the final consonant /n/ is voiced, the suffix is also voiced, becoming /z/ : /kɜ:rtənz/


a. Pronunciation (productive): The –s morpheme may be devoiced, resulting in */kɜ:təns/

b. Pronunciation (productive): In some languages the /k/ sound occurs but is not aspirated – eg French and, when the /k/ is in initial position, Italian. Learners of these L1 groups may be perceived as using a /g/ sound.(Source: Kenworthy, Teaching English Pronunciation, Longman)