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Ifyoudonotfindtherequiredinformationusingthetipsfromtheprevioussection,thenyouneedtoconsultanonlineservicetofindthepieceofinformationyouwerelookingfor.Threedifferenttypesofserviceshavebeenestablishedovertheyears:crawlers,directoriesandmetasearchengines.Thefirstcrawlerwascreatedbackin1993.ItwascalledtheWorldWideWorm.Itcrawledfromonesitetothenextandindexedallpagesbysavingthecontentofthewebpagesintoahugedatabase.Crawlersorspidersvisitawebpage,readit,andthenfollowlinkstootherpageswithinthesiteandevenfollowlinkstoothersites.Webcrawlersreturntoeachsiteonaregularbasis,suchaseverymonthortwo,tolookforchanges.Everythingacrawlerfindsgoesintoadatabase,whichpeopleareabletoquery.TheadvantageofthewebcrawlersisthattheyhaveanextensivedatabasewithalmostthecompleteInternetindexedinit.Thedisadvantageisthatyougetthousandsofwebpagesasaresponseforalmostanyrequest.Webdirectoriesworkalittledifferently.Firstofalltheycontainastructuredtreeofinformation.Allinformationenteredintothistreeiseitherenteredbythewebmasterwhowantstoannouncehisnewwebpageorbythedirectorymaintainerwholooksatthewebpagessubmitted.ThedirectorieswherewebmasterscansubmitboththeURL(UniformResourceLocator)andthedescriptionnormallycontainmoremisleadinginformation.Gettingintomostwebdirectoriesisacombinationofluckandquality.Althoughanyoneisabletosubmitawebpage,thereisnoguaranteethatacertainpagewillbeincluded.Somedirectorieschargeforsubmission,whichisbasicallyarip-off.Somecrawlersmaintainanassociateddirectory.Ifyoursiteisinthedirectory,therankingofyourwebsitenormallywillbehigher,asitisalreadypre-classified.Manydirectoriesworkwithcrawlerstogether,inordertodeliverresults,whennothingcanbefoundinthedirectory.MetasearchenginesdonothaveadatabasewithURLsanddescriptions.Insteadtheyhaveadatabaseofsearchengines.Ifyouenteryourkeywordsintoametasearchengineitwillsendoutrequeststoallthedirectoriesandcrawlersithasstoredinitsdatabase.ThemetasearchengineswithamoresophisticatedapplicationinthebackgroundareabletodetectdoubleURLswhichcomebackfromthevarioussearchenginesandpresentonlyasingleURLtothecustomer.
34.Crawlerisakindof__________.
A.wormB.searchengineC.serviceD.directory
35.ThedisadvantageofCrawleristhatit__________.
A.providesacompletedatabase
B.takestoomuchtimetofindtheneededinformation
C.providestoomuchuselessinformation
D.givesresponsetoeveryquest
36.Whocaninputinformationtothewebdirectories?
A.Onlywebmasters.
B.Bothdirectorymaintainersandwebmasters.
C.Anyonewhowantstoannounceawebpage.
D.Anyonewhohasfoundanewwebpage.
Relaxationtherapy(=treatment).Ifyoureadthesentenceoutloud,yourbloodpressurewillgoup.Ifyoutalktoanotherperson,itwillgostillhigher.Ifthetalkiswithyourboss,yourpressurewillgoevenhigher.Ifyouspeaktosomeoneoftheoppositesex,yourpressuremayshowlesschangeifyou’remarriedthanifyou’resingle.Dozensoftimeseachday,yourbloodpressurechangeswithwhatyou’refeelinganddoing.These“upsanddowns”takeplaceineveryone,buttheyaremoresevereinpeoplewithhighbloodpressure.Thatdiscoveryisthebasisforthenewesttherapy:controllingbloodpressurebylearningskillstocontroleverydaystress.Manypatientscontroltheirbloodpressurewiththerelaxationresponse.Thistakesfoursimplethings:aquietenvironment,acomfortableposition(sittingorlyingdown),therepeatingofaword,prayerorphraseeachtimeyoubreatheandhavingnoneofotherthoughts.Somethingremarkablehappenswhenyoudothis,accordingtoresearchinBoston.Relaxationofthemindandbodyhastheeffectthatsomeblood-pressurepillswouldhave.What’smore,thebloodpressurestayslower,justasitwouldwithapill,afteryouhavestoppedtherelaxationandhavereturnedtothestressofdailylife.
31.Thefirstparagraphtellsusthereasonwhyyourbloodpressuregoesupisthat__________.
A.youreadaloudasentence
B.themanyoutalktoisyourboss
C.you’renotmarried
D.you’renervous
32.Whichofthefollowingstatementsisnottrue?
A.One’sbloodpressurechangesmanytimeseveryday.
B.Yourbloodpressurechangeswithyourfeelings.
C.Whenyou’redoingdifferentthings,yourbloodpressure,perhaps,isdifferent.
D.Thechangesofbloodpressureonlyhappentopeoplewithhighbloodpressure.
33.Thelastparagraphtellsusrelaxationtherapy__________.
A.needsanewkindofmedicine
B.hasthesameeffectasblood-pressurepills
C.ismorethanblood-pressurepills
D.isworkingandcanbeimproved
