These guides assume you are comfortable with the Command Line, Git and Python. You must have all of these installed on your machine. You are also strongly encouraged to have a GitHub account. You are encouraged to fork or clone the Mother Tongues Dictionary Starter and follow along.
The most time-intensive part of building your dictionary, depending on how you want to publish it, is preparing your data.
It is recommended that you keep the following structure for your dictionary.
This demo uses 'danish' as the example language - you should replace all instances of 'danish' with your language.
The folder struture of the Mother Tongues Dictionary Starter follows this pattern which is part of why it's a good idea to use it to follow along.
MTD Language Configuration file
In the starter, the language configuration file is found here:
Every language must have a configuration file, and it must be validated
against the following schema
Below is a minimal Language Configuration file labelled
Adding your custom alphabet allows your entries to be sorted based on
that alphabet. If you don't use a custom alphabet, the English alphabet will be used instead.
In your Language Configuration file, set the
key equal to an array containing the letters in your language's
alphabet in alphabetical order:
You can also reference a file that contains a csv of your alphabet:
In the starter, an alphabet file is used at
MTD Data Resource Configuration file
In the starter, the data resource configuration file is found here:
Every data resource must have a configuration, and it must be validated against the following schema here.
Below is a minimal Data Configuration. This must be referenced in the language configuration above.
This configuration file describes a CSV dictionary resource that only has two columns where the first column includes the word in the target language and the second column includes the 'definition' of that word or 'gloss' in the L2 language.
In the future, I would like to have an online schema validation tool in the vein of SwaggerHub. Help with this is welcome!
To add information that can be optionally displayed in the UI, you must point to it in your Data Resource configuration file. For example, if you wanted to add "Part of Speech" information that could be displayed optionally and that was present in column "F" of an Excel spreadsheet, you would add the following to your Data Resource configuration file:
To add images and audio, you must have the filenames of your files in your dictionary data resource. Then, change your Data Resource configuration files to point to the location of the filenames.
For images, just add a target for the
img key. Take the following
example for an Excel spreadsheet with image filenames in column "D":
For audio, you minimally have to add the filename, but you can also add
a speaker name. You can also choose between
audio for audio files in
the target language,
definition_audio for audio files of the
example_sentence_audio for audio files corresponding to an
example sentence and
example_sentence_definition_audio for audio files
corresponding to the definitions of example sentences.
Take the following example for an Excel spreadsheet with audio in columns "B" & "C" and example sentence audio in column "D". The speaker names for audio files are in columns "E", "F", and "G" respectively.
To add semantic categories to your entries, you can make use of both the
secondary_theme keys in the Data Resource configuration
file. Using these will allow your entries to be sorted based on semantic
categories like "colours", or "animals" etc.
For example, suppose you have an Excel spreadsheet where column "A" has main categories like "Animals", and column "B" has sub-categories like "- Fish", and "- Reptiles". Your Data Resource congfiguration file would have to add the following targets:
Approximate search isn't just a nice feature for dictionaries of endangered languages - it's usually a requirement. Often, it's learners of languages that want to use dictionaries the most, and if your dictionary doesn't allow approximate search, beginners might have a hard time accessing entries in the dictionary.
How does it work?
Basically, you need to tell MotherTongues two things: a list of predictable mistakes, and a corresponding list of what characters the user likely meant to type instead.
The way you 'tell' MotherTongues these things is through the use of a character mapping file. MotherTongues makes use of the g2p Python Library which also has a corresponding website. As per the
g2p library, for each mapping, you need either a
json file, and an
yaml configuration file.
These files are in the mtd-starter repository at
A possible configuration file could look like this:
You might want to make these
mappings for a variety of reasons.
Typical learner/user mistakes come from the following issues:
- Learners have a hard time hearing the difference between sounds.
- Learners don't often know how to spell the different sounds.
- Some languages make it tricky to type, even if you can hear the difference and know how to spell the word.
See this paper for further discussion.
Creating a single mapping
For example, in Gitksan, a learner might have a difficult time hearing the difference between a
k (/k/ in the phonetic alphabet) and a
ḵ (/q/ in the phonetic alphabet). So, we can write a configuration file like so:
and a csv file (
gitksan-approx.csv) like so:
We then update the Data Resource configuration to include the following changes:
Creating a 'composite' mapping
To string multiple mappings together, we can use a 'composite' mapping. This is a json file that contains only a list of the names of the mappings.
So assuming a structure like with the following 'mappings' (also known as 'transducers'):
We then add all the mappings we want to a json file:
If we want to use this transducer in our dictionary, we then make the following changes to the Data Resource Configuration:
This is advanced! Don't be discouraged if you don't understand this. Have a look at Python lambda functions to get an idea of what's going on here.
You can write any lambda function instead of a transducer to process data. For example, to turn all words into upper case and store them as
upper_form, you would do the following:
Seeing your dictionary in action!
Once you have prepared a Language Configuration and Resource
Configuration files for each source of data, you need to let
mothertongues put it all together!
This will parse all of the data according to your specifications, combine all of your sources of data,
sort your data according to your alphabet, and generate the code necessary for your approximate search to work.
This guide assumes that you have worked through the steps to create a valid Language Configuration file and Data Resource Configuration files for each unique source of data. It also assumes you have a directory structure similar to the one described in this guide.
First, in the command line, run the
mtd prepare command. You will need to point this
command at the directory with your configuration files:
mtd prepare <directory path>
For example, if you are within your working directory:
mtd prepare .
If successful, you will see the message:
Next, you can run the app using
mtd run. This will run the app with
the default Mother Tongues mobile UI. You can view it at by going to http://localhost:5000/ in your browser.
If you just edit the configuration files in your clone/fork of the
mtd-starter repo and push the changes, the demo will be automatically built and available at