* @param lemma The target lemma.
*/
public void modifyBow(Lemma lemma) throws Exception {
ContainsLemmaFilter filter=new ContainsLemmaFilter("");
Corpus aux=new Corpus(corpus);
filter.filter(aux, lemma);
ArrayList<WSM> wsm=new ArrayList<WSM>();
for(Input document:aux.getDocuments())
{
wsm.addAll(this.kw.extractKeywords(document, 10, true));
}