grammar Verb {
  token TOP {
    <root>
    <ending>
  }
  token root {
    (w+) <?{ ~$0 (elem) @root }>
  {
  token ending {
    (w+) <?{ ~$0 (elem) @ending }>
  {
}

my @root = <go jump play>;
my @ending = <ing es s ed>;

my $string = "going";
my $match = Verb.parse($string);
.Str.say for $match<root>;