any of various tall perennial grasses of the genus Calamagrostis having feathery plumes; natives of marshland fens and wet woodlands of temperate northern hemisphere是什么意思_any of various tall perennial grasses of the genus Calamagrostis having feathery plumes; natives of marshland fens and wet woodlands of temperate northern hemisphere在线翻译_英语_读音_用法_例句