a foot soldier的用法和样例：
- He had had four years in the field as a foot soldier.
- A heavily armed foot soldier of ancient Greece.
- Following the decision to digitize the battlefield, radio communication equipment, night-vision goggles, and other electronic equipment become essential items in a foot soldier's backpack.
- a foot soldier armed with a musket.
- a pawn; a cat's-paw; a foot soldier