but主要作连词。
但它可作介词，副词\r but用作介词，表示“除了”意义，相当于except.例如：\r No one knows him but/except she. 除了她，没有人认识她。\r I have nothing to do but/except wait for her.\r I have no choice butexcept to wait for her.\r but用作副词，相当于only, 常译为“只不过，仅仅”。例如：He finished his homework but ten minutes ago.他十分钟前刚完成作业。
