How to create inflectional paradigms

Revision as of 19:36, 20 February 2013

Inflectional paradigms are sets of rules that are used to generate inflections out of the base forms. In the dictionary, we store only the base forms (e.g., "book" and "explain"); the inflections ("book/books", "explain/explains/explained/explaining" are generated through rules. These rules are of the A-rule (affixation rules) type.

Before starting, consider the following:

Do not duplicate paradigms.

Before creating a paradigm, check whether it is really necessary, i.e., whether there is no existing paradigm that may be used in order to generate the intended inflections.

Do not create paradigms for a single word.

Paradigms are used to describe the behavior of several words. If the behavior is irregular, i.e., it is restricted only to a single word, it should be described as an inflectional rule instead of an inflectional paradigm. For instance, the plural of the English word "foot" is better generated by an inflectional rule rather than by an inflectional paradigm. Inflectional rules are not included in the grammar. They are added directly to the dictionary entry, in the dictionary.

Do not include compound forms in your paradigm.

Paradigms must deal only with simple forms, i.e., forms that can be generated by prefixation, infixation or suffixation. In many cases, inflections are also generated by adding auxiliary or supporting words. These compound forms must not be included inside the paradigm, but should be handled by the grammar. For instance, in English, the simple present ("explain">"explain"/"explains") is defined inside the paradigm, but the present progressive and the future are not ("explain">"is explaining", "explain">"will explain") because they cannot be formed through suffixation. They require more complex structures and should be not treated as simple string manipulations (note that the negation, for instance, comes between the auxiliary and the main verb: "is NOT explaining", "will NOT explain", and this prevents the possiblity of treating "will explain" as a single string formed out of "explain" through the prefixation of "will ").

In order to create inflectional paradigms, follow the steps below:

1. Determine the inflectional categories for the part-of-speech.

   The inflectional categories describe the differences between the possible forms of the same lemma. Compare the examples below for the nouns, adjectives and verbs in English, French and Latin.

Important:

The same part-of-speech may involve different inflectional categories.

In French, for instance, some nouns, such as "livre", only inflect in number (SNG and PLR); other nouns, such as "ami", inflect in number and in gender (MCL&SNG,MCL&PLR,FEM&SNG,FEM&PLR).

Rules are not cumulative.

You have to combine inflectional categories in one same condition because it's not possible to apply rules sequentially. For instance, it's not possible, in French, to write simply FEM:=0>"e"; and PLR:=0>"s";. It's necessary to write FEM&PLR:=0>"es";. This happens because, for the time being, it's not possible to tell the machine in which order the rules should be applied. In this case, we could have "amise" instead of "amies".