What is the command given to extend the interval while marching?

The command "EXTEND, MARCH" is used to instruct a formation to increase the distance between individuals. This command helps create more space within the ranks, which can be important for various reasons, such as ensuring safety during movements, facilitating better visibility, and allowing for more freedom of movement for each Marine.

When the command is given, soldiers recognize it as an order to spread out while maintaining their alignment, which helps prevent crowding and maintains the formation's structure. The term "extend" specifically communicates the need for greater spacing, making it clear and comprehensive for soldiers to understand and act upon immediately. This command is also consistent with military terminology, as "extend" is a widely accepted term in drill and ceremony.