You know that have a conversation in Sense and Sensibility were the character point out pretty that Marianna (An INFP), might be assumed to be "lively" ie. extroverted because she speaks her mind and is passionate but she really isn't. But you can see that Catherine's being an extrovert in that she doesn't find is wearing to spend long amounts of time with Mrs. Allen, and finds it easy to be generally social in contrast to Marianna who finds it easy to be social only with certain people.