NL has an extremely rich form and structure.
It is very ambiguous. There can be different levels of ambiguity −
- Lexical ambiguity − It is at very primitive level such as word-level.
- For example, treating the word “board” as noun or verb?
- Syntax Level ambiguity − A sentence can be parsed in different ways.
- For example, “He lifted the beetle with red cap.” − Did he use cap to lift the beetle or he lifted a beetle that had red cap?
- Referential ambiguity − Referring to something using pronouns. For example, Rima went to Gauri. She said, “I am tired.” − Exactly who is tired?
- One input can mean different meanings.
- Many inputs can mean the same thing.
NLP Terminology
- Phonology − It is study of organizing sound systematically.
- Morphology − It is a study of construction of words from primitive meaningful units.
- Morpheme − It is primitive unit of meaning in a language.
- Syntax − It refers to arranging words to make a sentence. It also involves determining the structural role of words in the sentence and in phrases.
- Semantics − It is concerned with the meaning of words and how to combine words into meaningful phrases and sentences.
- Pragmatics − It deals with using and understanding sentences in different situations and how the interpretation of the sentence is affected.
- Discourse − It deals with how the immediately preceding sentence can affect the interpretation of the next sentence.
- World Knowledge − It includes the general knowledge about the world.