类别1 开头常用短语 It s said that... 据说…… As we all know that... 我们都知道…… It s well known that... 众所周知…… As/So far as I know... 据我所知…… It is clear/obvious that... ……是显而易见的 类别2 表“结构顺序” first/firstly 第一 first of all 首先 to begin/start with 首先 in the first place 首先 second/secondly 第二 next 其次;然后 and then 于是;然后 meanwhile/at the same time 同时 finally/eventually/at last/in the end 最终