Kanjika

A practical Ruby gem for Japanese verb conjugation. Kanjika provides an easy-to-use interface for conjugating Japanese verbs across multiple forms including masu (polite), te, and potential forms.

Installation

System Requirements

Kanjika requires MeCab (a Japanese morphological analyzer) to be installed on your system.

Ubuntu/Debian:

sudo apt-get install mecab libmecab-dev mecab-ipadic-utf8

macOS:

brew install mecab mecab-ipadic

Other systems: Please refer to the MeCab installation guide.

Gem Installation

Add this line to your application's Gemfile:

gem 'kanjika'

And then execute:

bundle install

Or install it yourself as:

gem install kanjika

Features

🎌 Japanese verb conjugation (multiple forms)
📝 Support for all verb types: Godan (五段), Ichidan (一段), and Irregular verbs
🔄 Multiple conjugation forms: te-form, masu-form, potential
🎯 Simple and intuitive API
⚡ Built on top of Ve and Mojinizer for accurate morphological analysis

Usage

Basic Conjugation

Kanjika provides two main ways to conjugate verbs:

Using the module-level method

require 'kanjika'

# Conjugate directly
Kanjika.conjugate("食べる", :masu)  # => "食べます" (tabemasu - eat/will eat)
Kanjika.conjugate("書く", :te)      # => "書いて" (kaite - write and...)

# Negative forms
Kanjika.conjugate("食べる", :masu, negative: true)  # => "食べません" (tabemasen - don't eat)
Kanjika.conjugate("食べる", :te, negative: true)    # => "食べなくて" (tabenakute - not eating/without eating)

Using the Verb object

verb = Kanjika.verb('書く')

# Get the masu form (polite present/future)
verb.conjugate(:masu)      # => "書きます" (kakimasu - write/will write)
verb.to(:masu)             # => "書きます" (alias)

# Get the te form (connective)
verb.conjugate(:te)        # => "書いて" (kaite - write and...)

# Get the potential form (can do)
verb.conjugate(:potential) # => "書ける" (kakeru - can write)

# Negative forms
verb.conjugate(:masu, negative: true)  # => "書きません" (kakimasen - don't write)
verb.conjugate(:te, negative: true)    # => "書かなくて" (kakanakute - not writing/without writing)

Supported Conjugation Forms

Masu Form (Polite Present)

Kanjika.conjugate("食べる", :masu)    # => "食べます" (tabemasu - eat/will eat)
Kanjika.conjugate("書く", :masu)      # => "書きます" (kakimasu - write/will write)
Kanjika.conjugate("する", :masu)      # => "します" (shimasu - do/will do)

# Negative
Kanjika.conjugate("食べる", :masu, negative: true)  # => "食べません" (tabemasen - don't eat)

Te Form (Conjunctive)

Kanjika.conjugate("食べる", :te)      # => "食べて" (tabete - eat and...)
Kanjika.conjugate("書く", :te)        # => "書いて" (kaite - write and...)
Kanjika.conjugate("飲む", :te)        # => "飲んで" (nonde - drink and...)
Kanjika.conjugate("買う", :te)        # => "買って" (katte - buy and...)

# Negative
Kanjika.conjugate("食べる", :te, negative: true)    # => "食べなくて" (tabenakute - not eating/without eating)

Potential Form (Can do)

Kanjika.conjugate("食べる", :potential)  # => "食べられる" (taberareru - can eat)
Kanjika.conjugate("書く", :potential)    # => "書ける" (kakeru - can write)
Kanjika.conjugate("飲む", :potential)    # => "飲める" (nomeru - can drink)
Kanjika.conjugate("する", :potential)    # => "できる" (dekiru - can do)

Verb Types

Kanjika handles all three types of Japanese verbs:

Godan Verbs (五段動詞)

Verbs that end in u-column sounds. Examples:

書く (kaku) - to write
飲む (nomu) - to drink
買う (kau) - to buy
話す (hanasu) - to speak

Ichidan Verbs (一段動詞)

Verbs that end in -eru or -iru. Examples:

食べる (taberu) - to eat
見る (miru) - to see
起きる (okiru) - to wake up

Irregular Verbs

Only two main irregular verbs:

する (suru) - to do
来る (kuru) - to come

Pronunciation Guide

To help beginners, we're adding pronunciation guides for the kanji used in this documentation and in the code.

食べる (taberu): to eat
書く (kaku): to write
飲む (nomu): to drink
買う (kau): to buy
話す (hanasu): to speak
見る (miru): to see
起きる (okiru): to wake up
する (suru): to do
来る (kuru): to come
五段 (godan): five-step (verb type)
一段 (ichidan): one-step (verb type)

Examples

# 食べる (taberu - to eat) - Ichidan
verb = "食べる"
Kanjika.conjugate(verb, :masu)       # => "食べます" (tabemasu - eat/will eat)
Kanjika.conjugate(verb, :te)         # => "食べて" (tabete - eat and...)
Kanjika.conjugate(verb, :potential)  # => "食べられる" (taberareru - can eat)

# 書く (kaku - to write) - Godan
verb = "書く"
Kanjika.conjugate(verb, :masu)       # => "書きます" (kakimasu - write/will write)
Kanjika.conjugate(verb, :te)         # => "書いて" (kaite - write and...)
Kanjika.conjugate(verb, :potential)  # => "書ける" (kakeru - can write)

# する (suru - to do) - Irregular
verb = "する"
Kanjika.conjugate(verb, :masu)       # => "します" (shimasu - do/will do)
Kanjika.conjugate(verb, :te)         # => "して" (shite - do and...)
Kanjika.conjugate(verb, :potential)  # => "できる" (dekiru - can do)

Development

After checking out the repo, run:

bundle install

Run the tests:

bundle exec rspec

Run the linter:

bundle exec standardrb

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/fagnerpereira/kanjika_gem.

Fork it
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request

Roadmap

Here are some of the features we're planning to add to Kanjika:

More Conjugation Forms: We'll be adding support for more conjugation forms, such as:
- Passive (e.g., 食べられる - taberareru)
- Causative (e.g., 食べさせる - tabesaseru)
- Volitional (e.g., 食べよう - tabeyou)
- Imperative (e.g., 食べろ - tabero)
Adjective Conjugation: Support for i-adjectives and na-adjectives.
Verb Transitivity: The ability to identify if a verb is transitive or intransitive.
Kanji Pronunciation: We will add comments to the code to help beginners with the pronunciation of unknown kanji.
Web Interface: A simple web interface to demonstrate the gem's capabilities.

License

The gem is available as open source under the terms of the MIT License.

Credits

Built with:

Ve - Japanese morphological analyzer
Mojinizer - Japanese character utilities

kanjika

Runtime