1、which通常用来询问在一个已知的范围内进行选择。常见用法有:选择其中一个："Which color do you prefer, red or blue?"询问某人/物： "Which of the students is absent today?"询问特定原因： "Which reason do you think is the most important?"限定性定语从句： "The book, which is on the table, is mine."疑问代词和疑问副词结合使用："Which way should I go?"
2、"where" 通常用来询问位置或地点。常见用法有:询问地点： "Where is the nearest gas station?"询问去处或来处： "Where did you go on vacation?"询问事情发生的地点： "Where did the accident happen?"定语从句： "The city where I was born is beautiful."引导地点状语从句： "I'll meet you where we first met."疑问副词结合使用： "Wherever are you going?"
3、"which" 和 "where" 都可以用来询问或描述位置或地点，但它们在用法上有所不同。"Which" 通常用来在一个已知的范围内进行选择，如 "Which book do you want to read?" (在已知的书架上选择一本书)。"Where" 通常用来描述位置或地点, 如 "Where is the library?" (描述图书馆的位置)。另外， "Where" 还可以用来询问去处或来处，如 "Where did you go on vacation?" 也可以引导地点状语从句 "I'll meet you where we first met.", "Which" 不能这样用。总之, 在已知范围内选择，用"Which", 描述位置或地点，用"Where"。
