1.IntroductionLanguagedevelopment,whichreferstocharacteristicsofalearner’soutputthatrevealsomepointorstagealongadevelopmentalcontinuum(Wolfe-Quintero,Inagaki&Kim,1998),movesalongthreedimensions:fluency,accuracyandcomplexity.Asopposedtotheothertwodimensions,linguisticcomplexity,consistingoflexicalcomplexity(alsocalledlexicalrichness)andsyntacticcomplexity,ismostrelevanttochangeandtheopportunitiesfordevelopmentandgrowthintheinterlanguagesystemandthuswillbetheresearchfocusofthecurrentstudy.1.1NeedforthestudyThoughagreatnumberofstudieshavebeencarriedouttoinvestigatelexicalrichnessorsyntacticcomplexityseparatelyathomeandabroad(Hunt,1970;Crowhurst,1980,1983;Laufer,1991,1994,1995,1998;Bardovi-Harlig,1992;Vermeer,2000;WuXudong&ChenXiaoqing,2000;Ortega,2003;LiuDonghong,2003;YuHua,2004;WenQiufang,2006a,b;QinXiaoqing,2007),studiesonthedevelopmentaltendencyofthelexicalrichnessandsyntacticcomplexityfromalongitudinalperspectiveaswellastheinteractionbetweenlexicalrichnessandcomplexity(Morris&Crump,1982)arescantyandfarfromconclusive.What’smore,asWen(2006a)claims,lexicalcharacteristicsandsyntacticcharacteristicshavebeenheavilyexploredinEFLwriting(Engber,1995;James,2002;Laufer,1991,1998;Shaw&Liu,1998;LiJingquan&CaiJingting,2001;NiLan，2000;WenQiufang,etc.,2003,2004)whilesimilarresearchesonthespokendataofEFLlearnersaremuchrarer(Vermeer,2000;WenQiufang,2006a,b).Accordingly,alongitudinalstudyonthechangesinChineseL2learners’vocabularyandsyntaxisnecessary.ThislineofstudyshouldbeundertakenintheChinesecontextalsobecausethecorollaryofitwillhavesignificantpracticalimplicationsforL2lexisandsyntaxinstruction.ItisknownthatChineseL2teacherslaymoreemphasisongrammaticalaccuracythanoncomplexitybothininstructingandassessingwriting,whichleadstoL2learners’morefrequentuseofsimplevocabularyandsyntacticstructures,adetrimenttotheirlanguagedevelopment.Atpresent,westilllackaclearpictureofthedevelopmentalpatternsoflexicalrichnessandsyntacticcomplexityforChineseL2learners,whichwillundoubtedlyshedlightonChineseL2teaching.1.2ResearchpurposeThisstudyisundertakenwiththeaimofexploringthedevelopmentalpatternsofL2learners’lexicalrichnessandsyntacticcomplexity.Specifically,thepurposeofthepresentstudyisthree-fold:firstly,torevealthedevelopmentalpatternsofL2learners’lexicalrichnessandsyntacticcomplexityacrossthreeyears;secondly,tocomparethegrowthratesoflexicalrichnessandsyntacticcomplexityintheiroraloutputatthetwointervals;thirdly,toexaminetherelationshipbetweentheL2learners’lexicalrichnessandtheirsyntacticcomplexityinthreeyearsrespectively.2.LiteraturereviewInthefieldofSecondLanguageAcquisition(SLA)research,languagecompetencecanbestudiedfromdifferentaspects.Asforproductivity,languagecompetencecanmovealongtwodimensions:lexicalcomplexity(alsocalledlexicalrichness)andsyntacticcomplexity.Additionally,accordingtoWolfe-Quinteroetal.(1998),complexitymeansthatawidevarietyorawiderangeofbothbasicandsophisticatedstructuresandwordsareavailableandcanbeaccessedquickly.InWolfe-Quintero’sdefinition,thefirsthalfreferstosyntacticcomplexitywhilethelatterreferstolexicalrichness.Thischapterconsistsofthreeparts.Thefirstpartfocusesonlexicalrichness,thesecondpartonsyntacticcomplexityandthethirdpartonproblemsinthepreviousstudies.2.1LexicalrichnessManyscholars(Linnarud,1986;Nihanani,1981;Hyltenstam,1988;Engber,1995)havedonesomeresearchesonl...
