Warning: file_put_contents(/www/wwwroot/ppbbbu/202081.com/cache/55eaf2a7f79d537abfc3e011361d8c27.txt): failed to open stream: No space left on device in /www/wwwroot/ppbbbu/202081.com/index.php on line 55 portal frame英英字典_portal frame剑桥英语解释_portal frame柯林斯英文解释_2020年的事情英文词典
1. N a frame, usually of steel, consisting of two uprights and a cross beam at the top: the simplest structural unit in a framed building or a doorway 龙门钢架[civil engineering]