VariabilityinlearnerlanguageLanguangeissystematic.Learnerusuallyusethesamegramma-ticalform,althoughthisisofendifferentfromthatusedbynative.Andlearnershavedifferenttypesoferrorandexpression,andusethemalternately.Eg.1.errorerrorTheboyeatanapple.Theboyeatinganapple.Eg.2.errorcorrectterget-languageTheboyeatanapple.Theboyeatsanapple.Solearnerlanguageissystematicsincethatvariabilityisalsosystematic.typesofvariabilityLearnervarytheiruseofL2accordingtoseveraltypesofvariability1.Lingusticconext2.Situationconext3.Psycholinguisticconext4.freevariability1.LingusticconextInonecontexttheyuseoneformwhileinothercontexttheyusealternateforms.Thecrucialelementandsomeotherconstituentinterchangefrequentlyinthelinguisticcontext.Eg.1.Theverbsaredependingontheadverboffrequency.Johnplayingfootball,(=Johnplayedfootballallthetime,Johnusuallyplayfootballeveryday.(=Johnusuallyplayedfootballeveryday.2.verb“be”andit’svariants“is,’s,omitted”Theteachernothere.Theteacherisonthereyesterday.Theteacherwasnotherenow.2.SituationconextL2learners=nativespeakersUsethelanguagedifferently(formalorinformal)indifferentsituations.Eg.1.tofriendsorsomeoneveryfamiliarto.(informal)Mykid’sarealpainthesedays.2.tosomeonenotveryfamiliarorthestrangers(formal)Mydaughtercanbeverytroublesomethesedays.3.PsycholinguisticconextPsycholinguisticconext–whetherthelearnershavetheopportunitytoplantheirpruduction.(timeisavailableornot)PlanneddiscourseVSUnplaneddiscourse1.Learneruseahighproportionofirregularlanguageformsintheunplannednarrativethanintheplannedone.2.Learnerusetheformscorrectlyintheplannedthantheunplannednarrative.Itisclearthatlearnersusethetargetlanguageisstronginfluencedbytheavailabilityofplanningtime.Examlpe:Joe’sadayplanningunplanningThismorningIgotupearly.Afterbreakfast,Ihelpedmomwithhousework.ThenIdidmyhomework.Thehomeworkwasveryinteresting,soIdiditwell.Intheafternoon,IplayedtabletenniswithmyfriendLingling,weenjoyedourselvesverymuch.IntheeveningIdidn’twatchTVwithmyparentsbecauseIpreparedmyselfforthenextday'slesson.Whatabusydaytoday!ThismorningIgetedupearly.Afterbreakfast,Ihelpmomwithhousework.ThenIdidmyhomework.Thehomeworkwereveryinteresting,soIdoeditwell.Intheafternoon,IplayedtabletenniswithmyfriendLingling,weenjoyedourselvesverymuch.IntheeveningIdon’twatchedTVwithmyparentsbecauseIpreparedmyselfforthenextday'slesson.Whatabusydaytoday!Learnertrytomapparticularformsontoparticularfuc-tion.Theytrytomaketheparticularform-fuctionmappingstocomformtothosefoundinthetargetlanguage.Intheseprocedure,theerrorsmakebythelearnersaresometimesrandom,sometimesnotjustrandom.randomlyNotrandomlyno+verb/don’t+verbMariananocomingtoday.Don’tsitinthatonechair.ORMariananocomingtoday.Don’tsitinthatonechair.Theirchoiceisdeter-mindedbyavarietyoffactorssuchaslingusticconextsituationconextandavailabilityofplan-ningtime.4.Freevariabilityfreevariabilityconstitutesanessentialstageintheacquistionofgrammaticalstructures.1.Acquiringasingleformanduseitforavarietyoffunctions.2.Acquireotherformsbutinitiallytheyusetheseinterchangeablywiththesimpleform.3.Starttousetheformssystematically4elimainatenon-targetformsandusethetargetlanguageformtoperformthesamefunctionasnativespeakers.eat(foruture,presentandpasttime)ate(forpasttime)ate(forpasttimeforminplanneddiscourse)eatesd(inplanneddiscourse)ate(consistentlytorefertopasttime.)