usually one person pretending to be someone else or trying to pose as another person. How about you, what do you think?
Examples:
"I'm using my older brother's computer because mine isn't working . . . "
Or
"This is Jim's wife and I want to give my point of view . . . "
Or
"Normally this is an adult-only forum, but I found my roommate's laptop logged onto this website and it seems interesting . . . "
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