Warning: file_put_contents(/www/wwwroot/ppbbu/52065.com/cache/740f11a02c8339a5ae60f2ef729a53f5.txt): failed to open stream: No space left on device in /www/wwwroot/ppbbu/52065.com/index.php on line 55 plumb-line英英字典_plumb-line剑桥英语解释_plumb-line柯林斯英文解释_伍贰汉英词典
1. N-COUNT A plumb line is a piece of string with a weight attached to the end that is used to check that something such as a wall is vertical or that it slopes at the correct angle. 铅垂线