You can know if someone is an introvert if they keep loving to stay indoors for no good

reason,many introverts also love to be alone so whenever you see someone that loves to be alone

then that could be a sign that he or she is an introvert,many introverts are nerds,so whenever

you see that nerd in your class there is high probability that he or she is an introvert,some

introverts love to stay at home and browse the internet or read alot of novels,when you see

someone who is so addicted to the internet,the person could be an introvert...