连接副词可分为两类，一类是用于连接句子或从句，常见的有therefore, besides, otherwise, however, moreover, still, thus, meanwhile等;另一类是用于引导从句或不定式，主要的有when, why, where, how 等。1.连接副词起连接两个句子或子句的作用如:however,moreover,consequently,hence,also,besides,,otherwise,therefore,thus,thereupon等等