To bewilder someone is to confuse them so thoroughly that they cannot think straight — not a small puzzlement but a lost, spinning feeling. It is stronger than 'confuse' and points at the person's whole state of mind rather than one misunderstanding: if a form confuses you, you got one question wrong; if a form bewilders you, you have no idea where to start. The word is nearly always used with a thing as the subject and a person as the object — the noise bewildered him, the rules bewilder new students, her reply bewildered me — because it describes an effect something has on you, not something you do on purpose. You will mostly meet it in its two adjective forms: bewildered (the person: 'a bewildered look') and bewildering (the thing: 'a bewildering number of choices'), plus the noun bewilderment. There is a feeling of being lost inside it that no synonym quite has, and that feeling is in the word's history: the old verb 'wilder' meant to lead someone astray into wild country, so to bewilder is to leave someone wandering in a wilderness with no path. That is why it fits big, overwhelming confusion — a strange city, a foreign hospital, a language you cannot follow — better than it fits a single tricky question. In register it is neutral to slightly formal: common in journalism and novels, less common in casual speech, where people just say 'totally confused' or 'lost'.

使人困惑、使人不知所措（比 confuse 更強，是那種整個人暈頭轉向、不知從何下手的迷惘感）。近似中文的「一頭霧水」「暈頭轉向」。