介词 + which 语法详解：修饰先行词的用法

介词 + which 是关系代词从句中的一种形式，用来修饰先行词，并在从句中充当主语、宾语等成分。常见的介词包括：in, on, at, by, for, with, to, from, of, about, etc. 例如：The book 'on which' I am working is very interesting. (介词 on 修饰先行词 book，which 在从句中作主语)