Complex sentence: Lee was born in York and signed for his first senior teamYork City in 1937 on the strike of midnight on his seventeenth birthday, seventeen being the youngest age that a player could sign a professional contract at the time.
Split into simpler sentences: Lee was born in York and signed for his first senior teamYork City in 1937. He put pen to paper on the strike of midnight on his seventeenth birthday, seventeen being the youngest age that a player could sign a professional contract at the time.