English grammar - Roger Berry 2012

B1.4 Problems with word classes
B1 Word classes
Section B Development

There are a number of general problems with a word-class approach to grammar:

□ there are classes that we are not sure about (e.g. numerals, interjections);

□ the distinction between some classes is not always clear, e.g. between pronouns and determiners (see A3), or between adverbs and prepositions (see A4);

□ many words do not meet all the criteria for membership listed above (e.g. a noncount noun such as money does not have a plural or a genitive), so we have a situation in which some words are more typical members of a word class than others. It is nowadays normal to talk of ’core’ or ’prototypical’ members of a word class, in contrast to ’peripheral’ or ’marginal’ members. See A4 for an illustration of this with adjectives.

□ some words are difficult to assign to any class, e.g. yes and no are generally said to be adverbs, but they have little in common with other members of that word class.

□ adverbs especially are a problem to define formally. See B4 for more details.

In addition there are many words that can belong to more than one class (e.g. change, round, back). This is not necessarily a problem, though; we can use the different word class labels to explain the way such words behave and how they are different from other words. And we will see that such uses often involve a difference in meaning, which corresponds to that in grammar.

A further issue follows on from this: is word class membership an inherent feature of words or a feature that is endowed by particular instances of use; i.e. should we say that information is a noun or that it is used as a noun in particular cases? Some linguists would argue that only the second approach is valid. In this book, however, I have generally followed the former, traditional approach; dictionary writers seem to have no problem assigning a word class (or more than one) to words in isolation.