详细解释:【计】 DOS内部命令:清除屏幕并将光标移至屏幕的左上角
英语解释：
名词 cl:
a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)同义词：chlorine, Cl, atomic number 17