a branch feet oxygen dioxide, water, and shadow into snow
oxygen is invisible_gas. air has not oxygen_nitrogen_and_carbon_dioxide treading_water is aquatic_body_movement. limb is branch. snow is crystalline_form_of_solid_water. dead_tree_branch is organic_matter. snow is two_feet_deep. foot is vertebrate_foot. air has oxygen_nitrogen_and_carbon_dioxide branch_water is water.