4.1.2 Causal CMs
In the dissertation,causal CMs are specifically related with result such as as a result,hence,consequently,reason such as because,for,therefore,for that reason and purpose such as for that purpose.In the reason-result relationship,the authors set up the expectations in the reason and a semantics of obligation in the result.In Example(42),establishing on the reason,i.e.,students’choices on majors,the result is obligated.In Example(43),the result fulfills the expectation set up in the reason i.e.,different motivations and goals of the two kinds of viewers.
(42)Since students choose majors with higher economic returns or good employment prospects,overseas higher education institutions may develop more programmes in these majors.(S,AEs)
(43)In recent years,the effectiveness of narrative persuasion has become a focus of researchers of E-E because the motivations and goals of the viewer of an entertainment narrative are very different from those of other social educational media.(H,ANEs)
In the chosen data,CMs introducing purpose are small in number,so they are not taken into consideration and this does not affect the results of the study.Table 4.2 lists the occurrences and frequencies of the typical causal CMs in the chosen data.
Based on Table 4.2,there are 16 grammatical devices for causal explanation.As a matter of fact,5 devices(e.g.because,for,as,since,in that)are used to introduce reasons while 11 devices(e.g.therefore,so,so that,hence,consequently,as a result,for this reason,accordingly,thus,thereby,then)are used to express effect or result.That is to say,in the chosen data,almost two thirds of the devices are used to express result rather than cause,indicating that the authors in EAPs tend to mark the effect or result in diverse ways rather than the cause.Nonetheless,when comparing the frequencies of devices for cause and effect,the findings demonstrate that CMs of cause take up a frequency of 100,while the CMs expressing effect occupy a frequency of 88.7.
Table 4.2 Occurrences and frequencies of typical causal CMs
Among the five devices introducing reasons,because(64.7 per 100,000 words)and since(21.3 per 100,000 words)are more frequently used.Because is the most typical causal CM used in the selected academic discourse.It is used to introduce reasons,which implicitly set up the expectation.In Example(44),the reason(minor clause)is a limited market demand and the way the result is achieved is obvious in the contradictory directions(major clause).The result realizes the expectation which is set up in the reason.That is to say,the expectation is fulfilled by“pulling the media in contradictory directions”in the example.Similarly,in Example(45),the result in the main clause fulfills the expectation which is established in the minor clause.
(44)...the state and markets often pull the media in contradictory directions because there is only a limited“market demand”for the party’s political propaganda.(H,ANEs)
(45)Because the AFD neurons do not directly innervate any of the HSP70-producing cells,the authors invoke a neuroendocrine signalling mechanism.(N,AEs)
Since expresses positive epistemic stance in that the clauses in its scope are considered as representing“factual”or presupposed information(Quirk et a1.,1972;Heinämäki,1975).It introduces some known information for readers,i.e.it implies a presupposition.Example(46)shows that“no formally independent channel”in the minor clause could be considered as the presupposition of a“party lack a solid institutional and legal basis”.
(46)Since there is no formally independent media channel outside of the official system nor legal protection for freedom of the press,public discourses alternative to that of the party lack a solid institutional and legal basis.(H,AEs)
Among the CMs introducing the result,therefore(18.4 per 100,000 words),hence(13.9 per 100,000 words),thus(19.5 per 100,000 words)and then(10.5 per 100,000 words)are the most frequently employed.They have the basic meaning of result(at the discourse level of facts),inference(at the level of knowledge),and actions(as opposed to motives)(Schiffrin,1987).In Examples(47)-(50),therefore,hence,thus and then embody personal meanings in that they could help to develop the authors’arguments which are based on the analysis and assessment of ideas in the previous clauses.By leading the result,they entails the semantics of obligation.
(47)In addition,infected gammarids are more photophilic than uninfected ones.Therefore,two aspects of the photic behavior are manipulated in infected individuals:a chronic component,the photophilic behavior,and a phasic component,the positive phototactism as a response to mechanical disturbance.(N,AEs)
(48)There were no significant differences between participants who indicated that they had seen the movie(N 1/4 66)and those who indicated that they had not seen it:transportation(F 1/42.65,p1/4.105)and identification(F 1/42.17,p1/4.143).Hence,the variable of viewing experience was not considered in further analyses.(H,ANEs)
(49)Indeed,research has demonstrated that different methods of estimating growth produce different results(Pike 1992),and some critics raise this point as reason to distrust value-added results generally(Banta and Pike 2007).Thus,it may be difficult to know which value-added model to choose and which results to trust,especially in the absence of information about the quality of measurement provided by different models.
(S,AEs)
(50)After the pre-test,students were given a further hour of instruction on academic essay introductions based on the rhetorical moves model.Then,at the end of the two-hour workshop,all participants wrote a second academic essay introduction(post-test).(S,AEs)
In Example(47),therefore explains why photic behavior are manipulated.Hence in Example(48)leads a semantic meaning of obligation in not considering the variable of viewing experience was not considered in further analyses.Thus in Example(49)explains the difficulty based on the researches in the minor clause.Similarly,then in Example(50)introduces an obligation to do the post-test.
All in all,by using causal CMs,the readers’expectations are fulfilled while the writers are explaining the cause and effect.Among the chosen causal CMs,those which introduce reasons are the most frequently used.