noun🔗Share水螅，水螅虫. Any of several small freshwater polyps of the genus Hydra and related genera, having a naked cylindrical body and an oral opening surrounded by tentacles."The science student peered through the microscope at the hydra, noting its cylindrical body and the tentacles waving around its mouth. "那个理科生透过显微镜仔细观察着水螅，记录着它圆柱形的身体和在嘴巴周围摇动着的触须。animalorganismbiologynatureChat with AIVocabulary GamePractice Reading
noun🔗Share九头蛇，希 Hydra 怪物。 A dragon-like creature with many heads and the ability to regrow them when maimed."The mythical hydra was a fearsome monster; if you cut off one of its heads, two more would grow back. "神话中的九头蛇是一种可怕的怪物；如果你砍掉它一个头，还会长出两个新的。mythologyanimalChat with AIVocabulary GamePractice Reading
noun🔗Share难题，多头蛇难题. A complex, multifarious problem or situation that cannot be solved easily and rapidly."Dealing with the bureaucratic paperwork for my visa felt like fighting a hydra; every time I completed one form, two more seemed to appear. "办理我的签证，那些官僚主义的文件就像在与一个多头蛇难题搏斗；每次我填写完一张表格，似乎总会冒出两张新的。situationChat with AIVocabulary GamePractice Reading
