Japanese↔English transfer grammar for machine translation
Switch branches/tags
Nothing to show
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.


The Ja↔En Machine-translation System contains two transfer grammars: one for each translation direction:

  • JaEn for Japanese-to-English
  • Enja for English-to-Japanese

These transfer grammars map Minimal Recursion Semantic (MRS) representations to/from the Jacy Japanese grammar and the English Resource Grammar (ERG).


In order to use these transfer grammars, you will need either the ACE or LKB (by itself or as part of LOGON) processor installed. You'll also want to install Jacy and the ERG (binaries are available at the ACE website, or the grammar source is available in LOGON at $LOGONROOT/lingo/erg/). For extending JaEn with automatically extracted transfer rules (see below), you'll need to install PyDelphin (for Python 2.7).



There are two flavors to JaEn: a core transfer grammar containing hand-built and dictionary-extracted transfer rules, and a larger grammar using transfer rules extracted from bilingual corpora.

Note: The following have been removed, as they were not actively used by the ACE-compiled version of JaEn:

  • mrs.binlm language model (used by the LKB)
  • perl/ tools for extracting transfer rules from EDICT

If they are needed, you can get them from the original LOGON repository at $LOGONROOT/uio/tm/jaen/.

JaEn Core

Compile the core JaEn grammar as follows (from the top-level directory):

ace -g jaen/ace/config-core.tdl -G jaen-core.dat

This grammar may not have good coverage, but it can be useful for debugging.

Extended JaEn

If you want to use the automatically extracted transer rules for JaEn, you use the utils/select-rule.py script to generate a subset of the rules that only includes those useful for some given sentences. The rules extracted by Haugereid and Bond 2012 are available in the data/ directory. It is called as follows:

python2 utils/select-rule.py WORKDIR [OPTION..] ITEM [ITEM..]

The WORKDIR parameter is a path to a working directory, which is where the output files are written. If you don't supply the --data and --jacy options (for the data and Jacy directories, respectively), it assumes they are at $WORKDIR/data and $WORKDIR/jacy respectively. Thus, the easiest way to get started is to use the top-level directory of this repository as WORKDIR and to symlink Jacy. E.g.:

ln -s ~/grammars/jacy jacy
python2 utils/select-rule.py . jacy/tsdb/skeletons/tanaka/tc-000/item

If all goes well, the single.selected.mtr and mwe.selected.mtr files are created. Move these under the jaen/ subdirectory and compile:

mv single.selected.mtr jaen/
mv mwe.selected.mtr jaen/
ace -g jaen/ace/config.tdl -G jaen.dat

You can use many more item files to get a more robust transfer grammar, but if it is too big, ACE may fail to compile it.

python2 utils/select-rule.py . jacy/tsdb/skeletons/tanaka/tc-{000..100}/item


There has not been any development on EnJa for a while, so it currently does not have an ACE config file. It may work with the LKB, but we have not tested this. We include the EnJa files so that we may update them in the future.


The JaEn and EnJa grammars were copied from the LOGON repository and now exist separately to encourage development. The original README is below:

this directory contains the LOGON Transfer Matrix (TM), an attempt at providing a reusable, basic infrastructure for the creation of new, language-specific transfer grammars. as of mid-2010, the core of the Transfer Matrix is straight from the original LOGON Norwegian--English MT system, with some additions from the experience of building Japanese--English and German--English prototypes.

between 2004 and 2010, the Transfer Matrix was maintained at the University of Oslo, predominantly by Stephan Oepen, Jan Tore Lønning, and Petter Haugereid. with the completion of the Paris release of the LOGON tree, TM maintenance is transferred to Nanyang Technological University (NTU), where Francis Bond and Petter Haugereid are actively working on transfer-based MT.


Francis Bond, Stephan Oepen, Eric Nichols, Dan Flickinger, Erik Velldal and Petter Haugereid (2011) Deep Open Source Machine Translation. In Machine Translation 25(2) 87-105 (bib)