1)表层次:
　　first／firstly ／to begin with ／in the first place
　　second／secondly／furthermore
　　third／thirdly／what is more／besides
　　 in addtion ／finally

　　2)表转折:
　　by contrast ／although ／though／ yet
　　at the same time ／but
　　despite／the fact that
　　even so ／in contrast
　　nevertheless ／even though
　　 for all that ／notwithstanding
　　on the contrary／ however in spite of
　　on the other hand ／otherwise
　　instead ／still ／regardless

　　3)表因果:
　　therfore ／consequently
　　because of／ for the reason
　　thus／ hence ／due to
　　owing to ／so ／accordingly
　　thanks to ／on this account ／since ／as
　　on that account ／in this way ／for ／as a result
　　as a consequence

　　4）表让步：
　　still ／nevertheless／in spite of ／all the same
　　of course ／despite ／even so ／after all

　　5)表递近：
　　furthermore ／moreover ／likewise ／what is more
　　besides ／also ／not only...but also...
　　too／ in addtion

　　6)表举例：
　　for example／ for instance
　　 for one thing／ that is
　　to illustrate as an illustration
　　a case in point

　　7)表解释：
　　as a matter of fact／ frankly speaking
　　 in this case ／namely
　　in other words

　　8)表总结：
　　in summary ／in a word ／thus ／as has been said
　　in brief ／in conclusion ／altogether／in other words
　　to conclude／ in fact／finally／ in simpler terms
　　indeed／ in short ／in particular
　　 that is ／in other words ／of course ／on the whole
　　namely ／in all／ therefore ／to summarize