The book Living with the Passive-Aggressive Man lists 11 responses that may help identify passive-aggressive behavior. 
- Ambiguity or speaking cryptically: a means of engendering a feeling of insecurity in others
- Chronically being late and forgetting things: another way to exert control.
- Fear of competition
- Fear of dependency
- Fear of intimacy as a means to act out anger: The passive aggressive often can’t trust. Because of this, they guard themselves against becoming intimately attached to someone.
- Making chaotic situations
- Making excuses
- Victimization response: instead of recognizing one’s own weaknesses.
A passive-aggressive person may not have all of these behaviors, and may have other non-passive-aggressive traits.
Reference : http://www.wikipedia.com
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