They generally consist of a hole in the ground with afootprint on either side.
它们由地上的一个洞、两边的一对脚印组成。
2
Installation of a patch or hotfix always leaves afootprint in the registry.
补丁程序或者修订程序的安装总是在注册表中留下痕迹。
3
Though afootprint can be positive or negative, the emphasis in these considerations is such that a person is seen primarily as a threat or load to the earth.