Morphological analysis is a foundational task in Natural Language Processing (NLP). It involves breaking down a word into its root and affix(es), which is essential for understanding word structure and meaning in any language.

1. Morphological Analysis

Morphological analysis involves breaking a word into its root and affix(es). Identifying the root of a word is a fundamental step in many NLP tasks.

Example: Word Forms Across Languages

• English:
  • Root: 'play'
  • Forms: 'play', 'plays', 'played', 'playing'
• Hindi:
  • Root: 'खेल' (khela)
  • Forms: खेल, खेला, खेली, खेलूंगा, खेलूंगी, खेलेगा, खेलेगी, खेलते, खेलती, खेलने, खेलकर
• Telugu:
  • Root: ఆడడం (Adadam)
  • Forms: ఆడుతాను, ఆడుతున్నాను, ఆడేను, ఆడేవా, ...

2. Morphological Richness

The number of forms a root word can take varies across languages. Indian languages are generally considered morphologically rich, meaning words can have many forms due to inflections and derivations.

3. Types of Morphology

Inflectional Morphology

• Deals with word forms of a root where there is no change in lexical category.
• Example: 'played' is an inflection of 'play' (both are verbs).

Derivational Morphology

• Deals with word forms of a root where there is a change in lexical category.
• Example: 'happiness' is a derivation of 'happy' (adjective → noun).

4. Morphological Features

During morphological analysis, each word is assigned a lexical category and may take suffixes for features such as gender, number, person, case, tense, aspect, and modality.

Nouns & Pronouns

• Can take suffixes for: gender, number, person, case

Example Analyses

Verbs

• Can take suffixes for: tense, aspect, modality, gender, number, person

Example Analyses

5. Feature References

• rt: root
• cat: lexical category (noun, verb, adjective, pronoun, adverb, preposition)
• gen: gender (masculine or feminine)
• num: number (singular (sg) or plural (pl))
• per: person (1, 2, or 3)
• tense: present, past, or future (for verbs)
• aspect: perfect (pft), continuous (cont), or habitual (hab) (for verbs)
• case: direct or oblique (for nouns)

Note:

• A case is oblique when a postposition occurs after a noun. If no postposition can occur after a noun, the case is direct.
• Some Hindi postpositions: का(kaa), की(kii), के(ke), को(ko), में(meM)

6. Summary

Morphological analysis is crucial for understanding and processing natural language, especially in morphologically rich languages like Hindi and Telugu. By breaking words into their roots and features, we can better analyze, translate, and generate language computationally.