1.2.3 Morphological criteria for determining category

Consider the set of words in (8) again. Alongside these we also have the related words:

Although some of these may sound strange concepts, they are perfectly acceptable forms. The idea–ideas case is the most straightforward. The distinction between these two words is that while the first refers to a single thing, the second refers to more than one of them. This is the distinction between singular and plural and in general this distinction can apply to virtually all nouns. Consider a more strange case: friendliness–friendlinesses. What is strange here is not the grammatical concepts of singular or plural, but that the semantic distinction is not one typically made. However, it is perfectly possible to conceptualise different types of friendliness: one can be friendly by saying good morning to someone as you pass in the street, without necessarily entering into a deeper relationship with them; other forms of friendliness may demand more of an emotional commitment. Therefore we can talk about different friendlinesses. By contrast, consider the following, based on the words in (9):

While not all of these words are ill formed by themselves, none of them can be considered to be the plural versions of the words in (9). These words simply do not have a plural form. Plural forms are restricted to the category noun and other categories do not have them.

What we have been looking at in the above paragraph is the morphological properties of words: the various forms we find for different words. Often morphemes constitute different pieces of words: the form ideas can be broken down into ‘idea’ and ‘s’, where the second piece represents the plural aspect of the word and is called the plural morpheme. The point is that only words of certain categories can host morphemes of certain types. Consider warms from (11). This, too, breaks down into two pieces, ‘warm’ and ‘s’. But the ‘s’ here is not the plural morpheme but another one which expresses something entirely different. This is the morpheme we get on words like hits, sees, kisses and imagines and it represents present tense, which has a number of meanings in English ranging from the description of what is taking place at the present moment to something that habitually happens:

Note that this morpheme cannot go in any of the words in (8) (except for weather, a fact that we will return to): ideas is not the present tense form of the word idea. Essentially then, different categories of words have different morphological properties and therefore one can distinguish between categories in terms of what morphemes they take: if it has a plural form, it is a noun and if it has a present tense form it is a verb.

It should be noted however, that there are a number of complications to the simple picture given above. First, it should be pointed out that morphological forms are not always uniformly produced. For example, compare the following singular and plural forms:

The first two cases in (13) represent the regular plural form in English, as we have been discussing. But even here there are differences. In the first case the morpheme is pronounced [z] whereas in the second it is pronounced [s]. This is a fact about English morpho-phonemics, that certain morphemes are unvoiced following an unvoiced consonant, that we will not go into in this book. However, this does show that what we are dealing with is something more abstract than simply pronunciations. This point is made even more forcefully by the third and fourth cases. The plural form men differs from the singular man in terms of the quality of the vowel and the plural form sheep is phonetically identical to the singular form sheep. From our point of view, however, the important point is not the question of how morphological forms are realised (that is a matter for phonologists), but that the morphological forms exist. Sheep IS the plural form of sheep and so there is a morphological plural for this word, which we know therefore is a noun. There is no plural form for the word warm, even abstractly, and so we know that this is not a noun.

What about cases like weather, where the form weathers can either be taken to be a plural form or a present tense form, as demonstrated by the following:

This is not an unusual situation and neither is it particularly problematic. Clearly, the word weather can function as either a noun or a verb. As a noun it can take the plural morpheme and as a verb it can take the present tense morpheme. There may be issues here to do with how we handle this situation: are there two entries in the lexicon for these cases, one for the noun weather and one for the verb, or is there one entry which can be categorised as either a noun or a verb? Again, however, we will not concern ourselves with these issues as they have little bearing on syntactic issues.