1、一、原 因 结 果例：There are probably +manyseveralthree+resonscauses+ for this +dramaticmarked+increasedeclinechange+ in.二、比 较 对 照例：There is no doubt thatObviously,+ it has itsboth+drawbacksdisadvantagesnegative effects+as well asand+meritsadvantagespositive effects.三、例 证例：We may +citequotementiontakepoint
2、out+a singlea commonanother+ example of.四、事 实例：No one can +denydoubtignoroverlook+ the +barehardessentialprofound+ fact that.五、数 据 调 查例：A +recentnewnationwide+studysurveypollinvestigation+conductedtaken+at a factoryby officials.六、权 威（专 家）例：As one +scientistwriterdoctorpsychologist+wrotecommentedpointed outnoted, .七、分 析例：It seems +quitealmost+(un)likely(im)possible(in)credible(in)conceivable+ that.
