Linguistics 105 * Words and Sounds

Lecture Number Eight

Morphological Conditional Variants

  1. Morphemes and Allomorphs.

    1. Analysis of a Morpheme. The past tense marker -ed in English has three pronunciations.


      walk [t]

      drag [d]

      pad [d]

      slip [t]


      pat [d]

      (a) [t] = Past Tense

      (b) [d] = Past Tense

      (c) [d] = Past Tense

      Because there is a phonetic similarity and a single meaning we want to show that there is a single morpheme here. However, if we posit that there is only one morpheme here, we must explain the variation in pronunciation by rule.

      If we can prove that the variation of form is independent of the definition of the morpheme, and that it is caused by environmental conditions rather than by differences in morphemes, we may conclude that example (1) shows three variations of the same morpheme.

      If we write out the rules in a manner similar to the phonological rules we've been using we find there are three options. (Here, the curly brackets are a device for reducing three rules to one representation.)

      If we assume that /-d/ is the morpheme, we need this rule to account for the allomorphs.

      If we assume that /-t/ is the morpheme, we need this rule to account for allomorphs.

      If we assume /-d/ is the basic morpheme, we need this rule to account for the allomorphs.

      Therefore, there are three ways to represent the allomorphy rules of the suffix -ed. But how do we know which form is basic and which are variants? (2a) reflects the historical development of English, since the suffix at one time was pronounced /ed/ after all verbs. However, speakers today do not know the history of English, and therefore do not use historical information when they choose variants. (For the time being we're describing the language synchronically.)

      Since the conditioning factor in all variations of (2) is a consonant, we should look to see which suffix occurs in contexts without a consonant, i.e. after a vowel.

      (3) agreed [grid]
        slowed [slod]
        stewed [st'yud]

      We want to use the rule that allows "no change" in the broadest range of contexts. So the underlying form here is /-d/.

    2. Modeling a Description of a Morpheme.

      Notice that the parenthesized information in each variation of (2) is redundant and may be omitted. That is, we may assume that if no variation takes place, the underlying form surfaces in speech without change. (While we liked to write "elsewhere in phonology problems, here we do not need to.) Our final allomorphy rule, based on the underlying morpheme /-d/, therefore, will look like example (4).

      There is no need to include the identity of /-d/ and /-d/ in our rule.

      But (4) represents the variation of the morpheme after it has been inserted into a context. In our description of our solution of this problem, it comes second. First, we must formulate a rule which accounts for the original presence of the suffix. This rule is very simple, using only the symbolic terms introduced in Lecture 6.

      (5) /-d/ / [TENSE: Past] _____ (Morpheme Insertion Rule)

      This rule stipulates that the morpheme /d/, designated as a suffix by the positioning of the hyphen, must be inserted after any and all lexical items with a tense feature set for the past tense. (We will assume that English 'Strong Verbs' like bring/brought, ring/rung, hit/hit contain some addition lexical feature which instructs the morphological component to ignore or circumvent this rule.)

      Remember: (5) is ordered before (4) in the grammar; the morpheme must be inserted before it is adjusted. This gives us a final form of the morphological rules as in example (6):

      (6a) /-d/ / [TENSE: Past] _____ (Morpheme Insertion Rule)

      This is the second, allomorphy, rule needed to explain the past tense morpheme in English.


    3. Inflectional versus Derivational Morphology

      1. Inflectional morphology is syntactic; it expresses syntactic relations
      2. Derivational morphology is lexical; it expresses lexical relations

        (7) The bak-er-'s hat : -er= derivational morpheme

        -'s= inflectional morpheme The -'s marks the external relation between baker and hat. The suffix -er marks the internal relation between baker and bake.

        An Eskimo (Yupik) example. Where is the line between derivation and inflection?

        qayuq "tea"  
        qayu-siq "teacup"
        Ins = Instrumental
        qayu-si-lun "tea set"
        Col= Collective
        qayu-si-lu-taq "teaset (storage) place"
        Loc= Locative
        "I quickly make a shelf for the teaset"
        Caus= Causative
        Conj1= Conjugation I
        1st/Sg= "I"

  2. Conclusion

    The way you distinguish the morpheme from its allomorphs is by finding the form which occurs in the greatest number of contexts. Often a morpheme varies depending upon the features of a stem consonant, and if there are approximately an equal number of consonants in each class involved, the underlying form will be the one which occurs before or after a vowel.

    There are two ways to distinguish lexical (derivational) morphology from inflectional. First, if there is a fundamental change in meaning caused by the addition of a morpheme, it is most probably a derivational morpheme. If, on the other hand, the morpheme changes because of some syntactic factor, e.g. something else in the phrase changes, it is definitely inflectional.
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