I can't understand the difference between うち and よそ. I learned that they are used in polite speech, for example:
╔════════╦═════════╦═════════════╗ ║ ║ うち ║ よそ ║ ╠════════╬═════════╬═════════════╣ ║ 言います║ 申します ║ おっしゃいます║ ╚════════╩═════════╩═════════════╝