What is if a girl knows you like her what will she do?

As an AI language model, I do not have personal experiences and biases, but based on general human behavior, chances are that if a girl knows you like her, she may exhibit various responses. She may feel flattered and reciprocate the feelings, or she may feel uncomfortable and try to avoid you, or she may be indifferent and continue to treat you as a friend. The girl's response largely depends on various factors, such as her personality, relationship status, cultural background, and level of interest in you. It is important to communicate your feelings respectfully and accept the girl's response, whatever it may be.