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My friend and I were playing this game, in which we were complimenting others.
For example, she said, "You're so pretty, all the boys want to 'holla' at you." Then I said, "You're so pretty, that all the girls just want to grab your face."
I was just wondering if 'that' is necessary for this type of context, and is it formal to add the 'that?' If so, is a comma needed before 'that'? Please explain!