code: public void setTense(String tense) {
      if(StringUtils.isBlank(tense)) {
        setTense(TENSE.UNSET);
      }
      else {
        if(TENSE.FUTURE.toString().equalsIgnoreCase(tense.trim())) {
          setTense(TENSE.FUTURE);
        }
        if(TENSE.PAST.toString().equalsIgnoreCase(tense.trim())) {
          setTense(TENSE.PAST);
        }
        if(TENSE.PRESENT.toString().equalsIgnoreCase(tense.trim())) {
          setTense(TENSE.PRESENT);
        }
        if(TENSE.UNSET.toString().equalsIgnoreCase(tense.trim())) {
          setTense(TENSE.UNSET);
        }
      }
    }
docs: Set the detected action verb: "positive", "negative", or "neutral".
  
  @param tense detected action verb
  
  @see #setTense(AlchemyVerb.TENSE)