He seems to take a ______ pleasure in punishing the least shortcomings. A: vengeful B: revengeful C: vindictive D: vindicative

The example of El A1 Airlines shows that ______. A: revengeful customers are a threat to the monopoly of enterprises B: an ad campaign is a way out for enterprises in financial difficulty C: a good slogan has great potential for improving service D: staff retraining is essential for better service