---
title: "Machine translation and challenges"
subject: "Artificial Intelligence"
chapter: 7
key: "semester_6/artificial_intelligence:machine-translation-challenges"
source: https://www.bctengineer.com/q/semester_6/artificial_intelligence/machine-translation-challenges
site: BCT Engineering
---

# Machine translation and challenges

Artificial Intelligence · Chapter 7: Application of AI

- Asked in: 2070 Bhadra, 1+7 marks
- Video: [5.3 Machine Translation in Artificial Intelligence](https://www.youtube.com/watch?v=to1Z_G06Ogs) — KnowledgeGATE Bytes
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/artificial_intelligence/machine-translation-challenges
- Whole chapter: https://www.bctengineer.com/md/semester_6/artificial_intelligence/chapter-7

## Question

Define machine translation in NLP. Explain the challenges of machine translation.

## Short answer

Machine translation automatically translates text between languages. Challenges include lexical/syntactic ambiguity, idioms, pronoun resolution, morphological differences, missing words, context, low-resource languages, named entities, fluency evaluation, and speech issues.

## Answer

**Machine translation (MT)** is the use of computer software to translate text or speech automatically from one natural language (source) to another (target), for example English to Nepali, while preserving the meaning.

Approaches: rule-based (direct, transfer, interlingua), statistical, and neural MT.

```text
 Source text -> Analysis -> Transfer/Interlingua -> Generation -> Target text
```

#### Challenges of machine translation
1. **Lexical ambiguity:** one word, many meanings. "Bank" (river or money), "bat" (animal or cricket bat). The right sense must be chosen.
2. **Structural (syntactic) ambiguity:** "I saw the man with a telescope" has two readings. Languages also differ in word order: English is SVO (Ram eats rice), Nepali is SOV (Ram bhat khanchha).
3. **Idioms and metaphors:** "kick the bucket" cannot be translated word by word.
4. **Pronoun and reference resolution:** "The trophy does not fit in the suitcase because it is too big": what is "it"?
5. **Morphological richness and gender/number/honorifics:** Nepali has several honorific levels (ta, timi, tapai) with no English equivalent.
6. **Missing words (lexical gaps):** a word in one language may have no single equivalent in the other (cultural terms such as "tika", "dashain").
7. **Context and pragmatics:** the same sentence can mean different things in different situations; sarcasm, tone.
8. **Low-resource languages:** little parallel text for languages like Nepali limits statistical and neural approaches.
9. **Named entities and transliteration:** names must be recognised and transliterated, not translated.
10. **Fluency and quality evaluation:** the output must be both accurate and natural; automatic evaluation (BLEU) is imperfect.
11. **Speech issues:** accent, noise and disfluencies for spoken translation.

## Check yourself

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

1. What is machine translation?
   A. Translating text or speech from a source language to a target language automatically while preserving meaning
   B. Translating a program from one programming language to another
   C. Converting speech to text only
   D. Storing a dictionary on a computer
   Answer: A. MT automatically translates natural-language text or speech from a source to a target language, preserving meaning. (Key point: Definition of MT)

2. Why is the word 'bank' a challenge for machine translation?
   A. It is a very long word
   B. It has no equivalent in any language
   C. It is a name that must be transliterated
   D. It has several meanings (river or money) and the right sense must be chosen
   Answer: D. This is lexical ambiguity: one word with many senses, so translation requires choosing the correct one. (Key point: Lexical ambiguity)

3. Which difference between English and Nepali makes translation harder?
   A. English is SOV and Nepali is SVO
   B. English is SVO and Nepali is SOV
   C. Both use the same word order
   D. English has honorifics and Nepali does not
   Answer: B. English is Subject-Verb-Object (Ram eats rice) while Nepali is Subject-Object-Verb (Ram bhat khanchha). (Key point: Word order difference)

## Related in other subjects

- [Segmentation; page table size; TLB](https://www.bctengineer.com/question.md?key=semester_6%2Foperating_system%3Asegmentation-address-bits-tlb) — Operating System, chapter 4