Give 'be' its past participle so toPastParticiple returns 'been'

src/2-two/preTagger/methods/transform/verbs/conjugate/index.js

@@ -20,6 +20,7 @@ const conjugate = function (inf, model) {
       Gerund: 'being',
       PastTense: 'was',
       PresentTense: 'is',
+      Participle: 'been',
     }
   }
   const [str, particle] = parse(inf)

tests/three/verbs/toPastParticiple.test.js

@@ -5,6 +5,9 @@ const here = '[three/verb-toPastParticiple] '
 test('toPastParticiple:', function (t) {
   const arr = [
     [`I eat breakfast every morning.`, `I have eaten breakfast every morning.`],
+    [`I am`, `I have been`],
+    [`She is happy.`, `She has been happy.`],
+    [`They are here.`, `They have been here.`],
     [`She reads a book before bed.`, `She has read a book before bed.`],
     [`He teaches math to high school students.`, `He has taught math to high school students.`],
     [`They walk their dog in the park.`, `They have walked their dog in the park.`],