U.S. Marines with 4th Assault Amphibian Battalion, 4th Marine Division, push forward in an assault amphibious vehicle at the mechanized assault course during Integrated Training Exercise 4-19 at Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 12, 2019. Marine Forces Reserve units participate in ITX to both complete annual training requirements and to increase unit readiness and proficiency. (U.S. Marine Corps photo by Lance Cpl. Preston L. Morris)