常用的关联词分为十一大类：
1.Additionin
addition，and，similarly，likewise，as well as，besides，furthermore，also，moreover，and then，too，not only ... but，even，besides this/that
2.Sequence
first(ly)，initially，second(ly) etc.，to begin with，then，next，arlier/later，after this/that following this/that，afterwards
3. Consequence
as a result，thus，so，therefore，constantly，it follows that，thereby，eventually，then，in that case，admittedly
4. Contrast
however，on the other hand，despite，in spiteof，though，although，but，on the contraryotherwise，yet，instead of，rather，whereas，nonetheless，even though，compared with，in contrast，alternatively
5. Certainty
obviously，certainly，plainly，of course，undoubtedly
6. Condition
if，unless，whether，provided that，for，so that，whether，depending on
7. Definition
is，refers to，means，that is，consists of
8. Summary
in conclusion，in summary，lastly，finally，to sum up，to conclude，to recapitulate，in short
9. Example
for instance，one example，for example，just as，in particular，such as，name to illustrate
10. Reason
since，as，so，because(of)，due to，owing to，the reason why，in other words，leads to
11. Time
before，since，as，until，meanwhile，at the moment，when，whenever，as soon as，just as
