---
description: "Handle multilingual content and language-specific processing including language identification and stop word management"
categories: ["workflows"]
tags: ["language-management", "multilingual", "fasttext", "stop-words", "language-detection"]
personas: ["data-scientist-focused", "mle-focused"]
difficulty: "intermediate"
content_type: "workflow"
modality: "text-only"
---

# Language Management

Handle multilingual content and language-specific processing requirements using NeMo Curator's tools and utilities.

NeMo Curator provides robust tools for managing multilingual text datasets through language detection, stop word management, and specialized handling for non-spaced languages. These tools are essential for creating high-quality monolingual datasets and applying language-specific processing.

## Before You Start

- The `FastTextLangId` filter (used with the `ScoreFilter` stage) requires a FastText language identification model file. Download `lid.176.bin` (or `lid.176.ftz`) from FastText: [Language identification](https://fasttext.cc/docs/en/language-identification.html).
- On a cluster, ensure the FastText model file is accessible to all workers (for example, a shared filesystem or object storage path).
- Provide newline-delimited JSON (`.jsonl`) with a `text` field, or set `text_field` in `ScoreFilter(...)`.
- For HTML extraction workflows (for example, Common Crawl), Curator uses CLD2 to provide language hints.

---

## How it Works

Language management in NeMo Curator typically follows this pattern using the Pipeline API:

```python
from nemo_curator.pipeline import Pipeline
from nemo_curator.stages.text.io.reader import JsonlReader
from nemo_curator.stages.text.filters import ScoreFilter
from nemo_curator.stages.text.filters.fasttext import FastTextLangId

# 1) Build the pipeline
pipeline = Pipeline(name="language_management")

# Read JSONL files into document batches
pipeline.add_stage(
    JsonlReader(file_paths="input_data/*.jsonl", files_per_partition=2)
)

# Identify languages and keep docs above a confidence threshold
pipeline.add_stage(
    ScoreFilter(
        FastTextLangId(model_path="/path/to/lid.176.bin", min_langid_score=0.3),
        score_field="language",
    )
)

# 2) Execute
results = pipeline.run()
```

---

## Language Processing Capabilities

- **Language detection** using FastText (176 languages) and CLD2 (used in HTML extraction pipelines)
- **Stop word management** with built-in lists and customizable thresholds
- **Special handling** for non-spaced languages (Chinese, Japanese, Thai, Korean)
- **Language-specific** text processing and quality filtering

## Available Tools

<Cards>

<Card title="Language Identification" href="/curate-text/process-data/language-management/language">
Identify document languages and separate multilingual datasets
fasttext
176-languages
detection
classification
</Card>

<Card title="Stop Words" href="/curate-text/process-data/language-management/stopwords">
Manage high-frequency words to enhance text extraction and content detection
preprocessing
filtering
language-specific
nlp
</Card>

</Cards>
