groundsheet

n waterproof sheet spread on the ground, eg under bedding in a tent 铺於地面的防水布（如帐篷内铺在被褥下者）.

grouch, grouchy, ground, ground control, ground crew, ground floor, ground rule, ground speed, ground staff, ground swell, ground-bait, ground-nut, ground-plan, ground-rent, grounded, grounding, groundless, groundlessly, grounds, groundsel, groundsman, groundwork, group, group captain, group practice, group therapy, groupie, grouping, grouse, grove, grovel, groveler, grovelling, grow, grow on, grow out of, grow up, grower, growing, growl,