How to create inflectional paradigms

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.

Warnings

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 ").

Steps

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

1. Create the inflectional schema, if it has not been created yet
2. Name the paradigm
3. Define the paradigm
4. Create the rules
5. Provide an exemplar form (to test the paradimg)
6. Provide examples

Create the inflectional schema

The inflectional schema is a template used to build paradigms and to assure that they will follow the same structure.
The inflectional schema is a list of inflectional categories for each part-of-speech. It describes the differences between the possible forms of the same lemma.
Consider the examples below for English, French and Latin.

English

In English, inflections concern only two part-of-speech: nouns and verbs. The others (determiners, adjectives, adverbs, etc.) are not inflectional.

Nouns

English nouns may have two forms: singular (SNG) and plural (PLR). Therefore, the inflectional schema for English nouns is the following:

• SNG (singular): table, man, foot
• PLR (plural): tables, men, feet

Verbs

English verbs may have several forms, but there are only 5 simple distinctive forms: infinitive (INF), gerund (GER), participle (PTP), simple past (PAS) and third person present indicative (3PS&PRS&IND). Therefore, the inflectional schema for English verbs is the following:

• INF (infinitive): love, do
• GER (gerund): loving, doing
• PAS (past): loved, did
• PTP (participle): loved, done
• 3PS&PRS&IND (third person singular present indicative): loves, does

Note, in the above, that the inflectional schema does not include simple present (PRS) because this uses the same forms of the infinitive. Note, also, that the only person informed is the third person singular (3PS) in case of present indicative (PRS&IND), because this is the only one that has a special behavior. Note, at last, that the schema does not include any compound tense (such as future, present progressive, present perfect, past perfect, etc.), because they cannot be generated through simple affixation.

French

In French, inflections affect nouns, adjectives and verbs.

Nouns

There are two types of French nouns: those that have only number inflection, and those that have number and gender. There will be, therefore, two inflectional schemes:

• Nouns inflecting only in number (such as "table" (=table), "ville" (=city), "voiture" (=car), "père" (=father), "dentiste" (=dentist), etc.)
  • SNG (singular): table, ville, voiture, père, dentiste
  • PLR (plural): tables, villes, voitures, pères, dentistes
• Nouns inflecting in number and gender (such as "ami" (=friend), "chien" (=dog), "danceur" (=dancer), etc.)
  • MCL&SNG (masculine singular): ami, chien, danceur
  • FEM&SNG (feminine singular): amie, chienne, danceuse
  • MCL&PLR (masculine plural): amis, chiens, danceurs
  • FEM&PLR (feminine plural): amies, chiennes, danceuses

Adjectives

In French, adjectives vary regularly in number and gender:

• MCL&SNG (masculine singular): beau
• FEM&SNG (feminine singular): belle
• MCL&PLR (masculine plural): beaux
• FEM&PLR (feminine plural): belles

Verbs

In French, verbs may have 51 different simple forms, such as the following:

• INF (infinitive): aimer
• PTP&MCL&SNG (participle masculine singular): aimé
• PTP&MCL&PLR (participle masculine plural): aimés
• PTP&FEM&SNG (participle feminine singular): aimée
• PTP&FEM&PLR (particile feminine plural): aimées
• 1PS&PRS&IND (first person singular present indicative): aime
• 2PS&PRS&IND (second person singular present indicative): aimes
• 3PS&PRS&IND (third person singular present indicative): aime
• 1PP&PRS&IND (first person plural present indicative): aimons
• 2PP&PRS&IND (second person plural present indicative): aimez
• 3PP&PRS&IND (third person plural present indicative): aiment
• 1PS&PAS&NPFV&IND (first person singular past imperfective indicative): aimais
• 2PS&PAS&NPFV&IND (second person singular past imperfective indicative): aimais
• 3PS&PAS&NPFV&IND (third person singular past imperfective indicative): aimait
• 1PP&PAS&NPFV&IND (first person plural past imperfective indicative): aimions
• 2PP&PAS&NPFV&IND (second person plural past imperfective indicative): aimiez
• 3PP&PAS&NPFV&IND (third person plural past imperfective indicative): aient
• etc. (see the complete list at French grammar)

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

   The inflectional categories describe the Compare the examples below for the nouns, adjectives and verbs in English, French and Latin.

language	category	base form	word forms	categories	rules
English	noun	book	book books	SNG PLR	SNG:=0>""; PLR:=0>"s";
French	noun	livre (=book)	livre livres	SNG PLR	SNG:=0>""; PLR:=0>"s";
French	noun	ami (=friend)	ami amis amie amies	MCL&SNG MCL&PLR FEM&SNG FEM&PLR	MCL&SNG:=0>""; MCL&PLR:=0>"s"; FEM&SNG:=0>"e"; FEM&PLR:=0>"es";

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, i.e., we could have "amise" instead of "amies", if we define the number and the gender separately.