Extraverts are people who are quiet, cautious, and less interactive with others.

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.

i believe your answer is:

quickly

i hope that : )