Distribution · linguistics

Lingua::EN::Conjugate

Divergent

English verb phrases from a bare verb and a pronoun — tense, modal, aspect, voice, negation and question order, as an ordered list of words.

Version: 0.3 zef:raku-community-modules
Depends: none beyond the core
License: Artistic-2.0
Its own test suite: 1 file, green
Checked: 2026-09-15 against Raku++ 3.28.0 and Rakudo 2026.08
Where it lives: raku.land · source

Install it #

$ rakupp install Lingua::EN::Conjugate

zef install Lingua::EN::Conjugate writes the same store; either installer leaves the module usable by both engines.

What it is for #

Generating English rather than parsing it: a template engine that needs "he goes" from go, a grammar drill, a text adventure that conjugates the verb the player typed. You hand it a bare verb and a pronoun subject; it hands back the words of the phrase, in order, as an Array.

Conjugating #

File

use Lingua::EN::Conjugate;

sub phrase(*%a) { conjugate(|%a).join(' ') }

say phrase(:bare<run>,  :subject<I>);
say phrase(:bare<run>,  :subject<he>);
say phrase(:bare<run>,  :subject<he>, :tense<sp>);
say phrase(:bare<go>,   :subject<she>, :tense<sp>, :forms['HaveEn']);
say phrase(:bare<eat>,  :subject<they>, :mod<will>, :forms['HaveEn', 'BeIng']);
say phrase(:bare<see>,  :subject<you>,  :tense<sp>, :forms['BeEn']);
say phrase(:bare<be>,   :subject<I>);
say phrase(:bare<have>, :subject<he>);

Output

I run
he runs
he ran
she had gone
they will have been eating
you were seen
I am
he has

Negation, contraction and question order:

File

use Lingua::EN::Conjugate;

sub phrase(*%a) { conjugate(|%a).join(' ') }

say 'negated        : ', phrase(:bare<run>, :subject<he>, :negation);
say 'contracted     : ', phrase(:bare<run>, :subject<he>, :negation, :shortneg);
say 'question       : ', phrase(:bare<run>, :subject<he>, :interrogative);
say 'both, short    : ', phrase(:bare<go>, :subject<you>, :negation, :shortneg, :interrogative);
say 'both, long     : ', phrase(:bare<go>, :subject<you>, :negation, :interrogative);
say '';
say 'the last line is ungrammatical — without :shortneg the question';
say 'word order is wrong. Use :shortneg with :interrogative.';

Output

negated        : he does not run
contracted     : he doesn't run
question       : does he run
both, short    : don't you go
both, long     : do not you go

the last line is ungrammatical — without :shortneg the question
word order is wrong. Use :shortneg with :interrogative.

The guard you will hit first #

The method's first statement returns [$bare] unless the subject is one of I you he she it we they and the tense is p or sp. Everything else is silently a no-op:

File

use Lingua::EN::Conjugate;

for <p sp i bi ing pp> -> $t {
    say sprintf('  tense=%-4s -> %s', $t,
                conjugate(:bare<go>, :subject<he>, :tense($t)).join(' '));
}
say '';
say '  subject=Bob -> ', conjugate(:bare<go>, :subject<Bob>).join(' ');
say '';
say 'so :tense<ing>, :tense<pp> and any non-pronoun subject give you the';
say 'bare verb back, with no error. Use :alias for a name — but note that';
say 'AGREEMENT still follows :subject:';
say '  he  + alias Bob -> ', conjugate(:bare<run>, :subject<he>,   :alias<Bob>).join(' ');
say '  they+ alias Bob -> ', conjugate(:bare<run>, :subject<they>, :alias<Bob>).join(' ');

Output

  tense=p    -> he goes
  tense=sp   -> he went
  tense=i    -> go
  tense=bi   -> go
  tense=ing  -> go
  tense=pp   -> go

  subject=Bob -> go

so :tense<ing>, :tense<pp> and any non-pronoun subject give you the
bare verb back, with no error. Use :alias for a name — but note that
AGREEMENT still follows :subject:
  he  + alias Bob -> Bob runs
  they+ alias Bob -> Bob run

The one thing to know #

The consonant-doubling rule needs four letters, so every three-letter CVC verb is mis-inflected — and four-letter ones are fine, which is exactly why the obvious test cases pass.

File

use Lingua::EN::Conjugate;

say 'progressive (should double the final consonant):';
for <run sit get put stop plan begin travel> -> $v {
    say sprintf('  %-8s -> %s', $v,
                conjugate(:bare($v), :subject<I>, :forms['BeIng']).join(' '));
}
say '';
say 'simple past, same rule:';
for <hug plan offer visit open benefit> -> $v {
    say sprintf('  %-8s -> %s', $v,
                conjugate(:bare($v), :subject<he>, :tense<sp>).join(' '));
}
say '';
say 'the rule is / (.+ <consonant> <stressedw>) (<consonant>) $$/ — the `.+`';
say 'demands a character BEFORE the C-V-C, so the shortest verb it can fire';
say 'on is four letters. It is stress-blind in the other direction too,';
say 'which is where offerred, visitted and openned come from.';

Output

progressive (should double the final consonant):
  run      -> I am runing
  sit      -> I am siting
  get      -> I am geting
  put      -> I am puting
  stop     -> I am stopping
  plan     -> I am planning
  begin    -> I am beginning
  travel   -> I am travelling

simple past, same rule:
  hug      -> he huged
  plan     -> he planned
  offer    -> he offerred
  visit    -> he visitted
  open     -> he openned
  benefit  -> he benefitted

the rule is / (.+ <consonant> <stressedw>) (<consonant>) $$/ — the `.+`
demands a character BEFORE the C-V-C, so the shortest verb it can fire
on is four letters. It is stress-blind in the other direction too,
which is where offerred, visitted and openned come from.

The irregular table has its own errors, and the flagship is the past participle of know:

File

use Lingua::EN::Conjugate;

for <know stride leap bear get dive burn> -> $v {
    say sprintf('  %-8s sp: %-14s pp: %s', $v,
        conjugate(:bare($v), :subject<he>, :tense<sp>).join(' '),
        conjugate(:bare($v), :subject<he>, :tense<sp>, :forms['HaveEn']).join(' '));
}
say '';
say 'know -> "had know": the participle field is missing its n.';
say 'the table also mixes dialects without saying so — gotten and dove are';
say 'American, burnt and travelling British.';

Output

  know     sp: he knew        pp: he had know
  stride   sp: he strod       pp: he had stridden
  leap     sp: he lept        pp: he had lept
  bear     sp: he bore        pp: he had born
  get      sp: he got         pp: he had gotten
  dive     sp: he dove        pp: he had dived
  burn     sp: he burnt       pp: he had burnt

know -> "had know": the participle field is missing its n.
the table also mixes dialects without saying so — gotten and dove are
American, burnt and travelling British.

Where the two engines differ #

One parse-level gap, and it lands squarely on this module's API: Raku++ cannot parse mod=> with no space before the fat arrow, and mod is the name of one of the named parameters.

File

use Lingua::EN::Conjugate;

# the portable spellings
say 'with :mod<will>   : ', conjugate(:bare<go>, :subject<she>, :mod<will>).join(' ');
say 'with mod => "may" : ', conjugate(:bare<go>, :subject<she>, mod => 'may').join(' ');
say '';
say 'the tight `mod=>"will"` does not parse under Raku++ — `mod`, `div`,';
say '`gcd` and `lcm` are read as operators in term position there. Put a';
say 'space in, or use the colonpair form.';
say '';
say 'an unknown modal is silent on both engines:';
say '  :mod<must> -> ', conjugate(:bare<go>, :subject<she>, :mod<must>).raku;
say '  an Any is pushed into the word list.';

Output

with :mod<will>   : she will go
with mod => "may" : she may go

the tight `mod=>"will"` does not parse under Raku++ — `mod`, `div`,
`gcd` and `lcm` are read as operators in term position there. Put a
space in, or use the colonpair form.

an unknown modal is silent on both engines:
  :mod<must> -> ["she", Any, "go"]
  an Any is pushed into the word list.

The other divergence is scoping: the file-scope sub is-erregular (spelled with two r's) carries no is export, so it is a compile error under Rakudo and callable under Raku++, where a module's unexported subs leak into the using scope. Reach it as the method .is-erregular on englishverb, which is portable — and remember it is a lookup in the irregular table, not a linguistic judgement.