noun🔗Share水螅，水螅属动物。 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."In the aquarium, the hydras, tiny, tube-shaped creatures with tentacles, clung to the glass and waited to catch small food particles floating by. "在水族箱里，那些像小管子一样、长着触须的水螅紧紧地吸附在玻璃上，等待捕捉漂浮过来的细小食物颗粒。organismanimalbiologynatureChat with AIVocabulary GamePractice Reading
noun🔗Share九头蛇，希 Hydra，多头蛇 A dragon-like creature with many heads and the ability to regrow them when maimed."The video game featured monstrous hydras that grew two heads for every one you cut off. "这款游戏中有一种可怕的怪物叫做九头蛇，你砍掉一个头，它反而会再长出两个来。mythologysupernaturalstoryanimalinhumanChat with AIVocabulary GamePractice Reading
noun🔗Share多头蛇，难以解决的难题。 A complex, multifarious problem or situation that cannot be solved easily and rapidly."Dealing with student absences can feel like battling hydras; every time you solve one absence issue, two more pop up. "处理学生缺勤问题就像在与多头蛇搏斗一样；每次你解决了一个缺勤问题，就会冒出两个新的问题。situationChat with AIVocabulary GamePractice Reading
