Complex sentence: Having been organized for possible deployment to Europe in the event that hostilities resumed, the 15th Marines remained on garrison duty in the Dominican Republic and was deactivated on August 1,1922, and its assets were absorbed into the 1st and 4th Regiments.
Split into simpler sentences: Having been organized for possible deployment to Europe in the event that hostilities resumed, the 15th Marines remained on garrison duty in the Dominican Republic. It was deactivated on August 1,1922 and its assets were absorbed into the 1st and 4th Regiments.