of,belonging to,or being the geologic time,system of rocks,and sedimentary deposits of the fifth period of the Paleozoic Era,characterized by the submergence of extensive land areas under shallow seas是什么意思_of,belonging to,or being the geologic time,system of rocks,and sedimentary deposits of the fifth period of the Paleozoic Era,characterized by the submergence of extensive land areas under shallow seas在线翻译_英语_读音_用法_例句