---
title: "NLP issues with example"
subject: "Artificial Intelligence"
chapter: 7
key: "semester_6/artificial_intelligence:nlp-issues"
source: https://www.bctengineer.com/q/semester_6/artificial_intelligence/nlp-issues
site: BCT Engineering
---

# NLP issues with example

Artificial Intelligence · Chapter 7: Application of AI

- Asked in: 2070 Magh, 2+6 marks
- Video: [What is NLP (Natural Language Processing)?](https://www.youtube.com/watch?v=fLvJ8VdHLA0) — IBM Technology
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/artificial_intelligence/nlp-issues
- Whole chapter: https://www.bctengineer.com/md/semester_6/artificial_intelligence/chapter-7

## Question

What is Natural Language Processing (NLP)? Discuss the different issues related with NLP with example.

## Short answer

NLP issues include lexical, syntactic, semantic, pragmatic ambiguity, anaphora, idioms, ill-formed input, ellipsis, world knowledge, language variation, and speech issues like homophones.

## Answer

**Natural language processing (NLP)** is the area of AI that lets computers understand and generate human language (text or speech) so people can communicate with computers naturally.

#### Issues (difficulties) in NLP
1. **Lexical ambiguity:** one word has several meanings or parts of speech. "Bank" (river bank / money bank), "book" (noun / verb).
2. **Syntactic (structural) ambiguity:** a sentence has more than one parse. "I saw the man with the telescope" (who has the telescope?). "Old men and women" (are the women old?).
3. **Semantic ambiguity:** the meaning is unclear even with a fixed parse. "The chicken is ready to eat."
4. **Pragmatic ambiguity:** meaning depends on context or speaker intent. "Can you open the door?" is a request. "Great weather!" in the rain is sarcasm.
5. **Anaphora and reference:** pronouns need antecedents. "Ram told Hari that he won" (he = Ram or Hari?).
6. **Idioms, metaphors and figurative language:** "It is raining cats and dogs."
7. **Ill-formed input:** spelling mistakes, grammar errors, slang, abbreviations, code mixing (Nepali written in Roman letters).
8. **Ellipsis and incompleteness:** "Ram likes tea and Hari coffee" (omitted verb).
9. **World knowledge and common sense:** "The city council refused the demonstrators a permit because they feared violence" needs knowledge to resolve "they".
10. **Variation across languages and dialects:** different word orders, scripts, rich morphology, few resources for languages like Nepali.
11. **Speech issues:** accents, noise, homophones ("their/there", "to/two").

Solving these needs lexicons, grammars, context, world knowledge and statistical/learning methods.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. 'I saw the man with the telescope' is an example of which issue?
   A. Lexical ambiguity
   B. Syntactic (structural) ambiguity, since it has more than one parse
   C. Ill-formed input
   D. Ellipsis
   Answer: B. The sentence can be parsed in two ways (who has the telescope), which is structural ambiguity. (Key point: Syntactic ambiguity)

2. Which example shows lexical ambiguity?
   A. 'Ram told Hari that he won'
   B. 'It is raining cats and dogs'
   C. 'Ram likes tea and Hari coffee'
   D. 'Book' as a noun and as a verb, or 'bank' as river bank and money bank
   Answer: D. Lexical ambiguity means a single word has several meanings or parts of speech. (Key point: Lexical ambiguity)

3. 'Ram told Hari that he won.' Which issue does this illustrate?
   A. Anaphora: the pronoun 'he' needs an antecedent (Ram or Hari)
   B. Pragmatic ambiguity of sarcasm
   C. Ellipsis of a verb
   D. Speech homophones
   Answer: A. A pronoun must be linked to what it refers to; here it is unclear whether 'he' is Ram or Hari. (Key point: Anaphora)

4. 'Ram likes tea and Hari coffee' shows which difficulty?
   A. Idiom
   B. Ellipsis, where a word (the verb) is omitted
   C. Homophone
   D. Morphological richness
   Answer: B. Ellipsis is omission of words; the verb 'likes' is left out in the second clause and must be inferred. (Key point: Ellipsis)

## Related in Artificial Intelligence

- [NLP and its steps](https://www.bctengineer.com/question.md?key=semester_6%2Fartificial_intelligence%3Anlp-steps) — Artificial Intelligence, chapter 7, asked 6×
- [NLU and NLG; NLP steps](https://www.bctengineer.com/question.md?key=semester_6%2Fartificial_intelligence%3Anlu-nlg-nlp-steps) — Artificial Intelligence, chapter 7
- [Syntactic, semantic, pragmatic analysis](https://www.bctengineer.com/question.md?key=semester_6%2Fartificial_intelligence%3Anlp-syntactic-semantic-pragmatic) — Artificial Intelligence, chapter 7

## Related in other subjects

- [High level languages and natural language](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Ahll-similar-natural-language) — Computer Programming, chapter 1
- [Regulatory issues in wireless communication](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Aregulatory-issues) — Wireless Communication, chapter 1, asked 6×
- [Centralized vs distributed; design issues](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Acentralized-vs-distributed) — Distributed System, chapter 1
- [PID tuning and computer control issues](https://www.bctengineer.com/question.md?key=semester_6%2Fembedded_system%3Apid-tuning-practical-issues) — Embedded System, chapter 7