一、并列句
用连接词连接两个句子，逗号不能连接两个句子二、常见连词
平行关系连词：and, not only…but also…, either…or…, neither…nor…, both and…
介词/副词：as well as, at the same time, in the meanwhile, likewise, similarly, equally…转折关系
连词：but, yet, while, whereas
介词/副词：however, nevertheless, unfortunately, unexpectedly, conversely, on the contrary, by contrast…选择关系
连词：or, whether…or…
介词/副词：alternatively…因果关系
连词：so, for
介词/副词：therefore, thus, consequently, as a result递进关系
连词：then
介词/副词：besides, furthermore, moreover, additionally, subsequently, in addition
Tips:
上下句之间如果有逻辑关系，一定加关系词
连接副词/介词不能连接两个句子，可以用 and+连接介词/副词
有连词的句子一般连词后有省略，连词后省略的成分连词前一定有。
