public override NLGElement BuildElement()
{
// The CoreNLP constituency parser may return a clause with no predicate, or no subjects.
// If that happened, it should have been taken care of during the Configure() process.
// Once we get to this point, assume we have a predicate and at least one subject.
Clause.subj = Subjects.Select(subject => subject.BuildElement()).ToArray();
Clause.vp = PredicateBuilder.BuildElement();
return(Clause);
}