Complex sentence: A native from the planet Liberté, Jeanne sometimes has a tendency to follow her heart and act rashly, much to the chagrin of her superiors, who consider her to be an embarrassment to the army, believing that she does not take her duty seriously.
Split into simpler sentences: A native from the planet Liberté, Jeanne has a tendency to follow her heart and act rashly. Her superiors consider her to be an embarrassment to the army because they feel that she does not take her duty seriously.