1 to find it difficult to speak or act (usually in a difficult or embarrassing situation) 支吾以对；不知所措: The questions they asked her at the interview had her floundering helplessly. 他们在面试中问她的问题令她茫然，不知应对。

2 to have a lot of problems and be in danger of failing completely 面临很多问题、有完全失败之虞: By the late nineties, the business was floundering. 九十年代末期，那家企业濒于倒闭。

3 to move with difficulty, for example when trying to get out of some water, wet earth, etc 举步维艰，挣扎（如在水里、泥泞里等）