副词是指表示状态或特征的词，用以修饰动词、形容词、其他副词或整个句子，包括时间、地点、程度、方式，结果，原因，目的等状态或特征。
副词大体可分为以下类型：
时间副词，如 now, then, today, presently,once
频率副词，如 often, always, seldom, never,sometimes
地点副词，如 here, there, everywhere, somewhere, home
方式副词，如carefully, properly (适当地), anxiously (焦虑地), suddenly,normally (正常地),
程度副词，如much, little, very, rather, too, still,
疑问副词，如 when, where, how, why
连接副词，如therefore, moreover, besides, however, otherwise(另外的
关系副词，如 when, where, why
顺序副词，如first, then, next, finally, afterwards。