Describing a person's behavior concretely, using action verbs -- for example, "Sam hit her friend" -- typically signals that the behavior is a one-time occurrence and not necessarily characteristic of that person. Describing someone's behavior using adjectives and nouns, on the other hand -- for example, "Sam is violent" -- comes across as more abstract and suggests that the behavior may reflect a personal trait. Prior research has also demonstrated that we tend to use these linguistic subtleties in a favorable way when we're talking about people who belong to the same group as us: We're likely to use abstract language in discussing their desirable behaviors and concrete language in describing their undesirable behaviors. If we're talking about someone from another group, however, the pattern reverses -- we tend to use concrete language to describe positive behaviors, and abstract language to describe negative ones. - www.sciencedaily.com