Part　I　Reading　Comprehension　


Questions　01-05　are　based　on　the　following　passage:　


The　concept　of　culture　has　been　defined　many　times,　and　although　no　definition　has　achieved　universal　acceptance,　most　of　the　definitions　include　three　central　ideas:　that　culture　is　passed　n　from　generation　to　generation,　that　a　culture　represents　a　ready-made　prescription　for　living　and　for　making　day-to-day　decisions,　and,　finally,　that　the　components　of　a　culture　are　accepted　by　those　in　the　culture　as　good,　and　true,　and　not　to　be　questioned.　The　eminent　anthropologist　George　Murdock　has　listed　seventy-three　items　that　characterize　every　known　culture,　past　and　present.　The　list　begins　with　Age-grading　and　Athletic　sports,　runs　to　Weaning　and　Weather　Control,　and　includes　on　the　way　such　items　as　Calendar,　Firemaking,　Property　Rights,　and　Toolmaking.　I　would　submit　that　even　the　most　extreme　advocate　of　a　culture　of　poverty　viewpoint　would　readily　acknowledge　that,　with　respect　to　almost　all　of　these　items,　every　American,　beyond　the　first　generation　immigrant,　regardless　of　race　or　class,　is　a　member　of　a　common　culture.　We　all　share　pretty　much　the　same　sports.　Maybe　poor　kids　dont　know　how　to　play　polo,　and　rich　kids　dont　spend　time　with　stickball,　but　we　all　know　baseball,　and　football,　and　basketball.　Despite　some　misguided　efforts　to　raise　minor　dialects　to　the　status　of　separate　tongues,　we　all,　in　fact,　share　the　same　language.　There　may　be　differences　in　diction　and　usage,　but　it　would　be　ridiculous　to　say　that　all　Americans　dont　speak　English.　We　have　the　calendar,　the　law,　and　large　numbers　of　other　cultural　items　in　common.　It　may　well　be　true　that　on　a　few　of　the　seventy-three　items　there　are　minor　variations　between　classes,　but　these　kinds　of　things　are　really　slight　variations　on　a　common　theme.　There　are　other　items　that　show　variability,　not　in　relation　to　class,　but　in　relation　to　religion　and　ethnic　background-funeral　customs　and　cooking,　for　example.　But　if　there　is　one　place　in　America　where　the　melting　pot　is　a　reality,　it　is　on　the　kitchen　stove;　in　the　course　of　one　month,　half　the　readers　of　this　sentence　have　probably　eaten　pizza,　hot　pastrami,　and　chow　mein.　Specific　differences　that　might　be　identified　a　signs　of　separate　cultural　identity　are　relatively　insignificant　within　the　general　unity　of　American　life;　they　are　cultural　commas　and　semicolons　in　the　paragraphs　and　pages　of　American　life.　


01.　According　to　the　authors　definition　of　culture,　____　.　
A.　a　culture　should　be　accepted　and　maintained　universally　
B.　a　culture　should　be　free　from　falsehood　and　evils　
C.　the　items　of　a　culture　should　be　taken　for　granted　by　people　
D.　the　items　of　a　culture　should　be　accepted　by　well-educated　people　
02.　Which　of　the　following　is　NOT　true　according　to　the　passage?
A.　Baseball,　football　and　basketball　are　popular　sports　in　America.　
B.　Pizza,　hot　pastrami,　and　chow　mein　are　popular　diet　in　America.　
C.　There　is　no　variation　in　using　the　American　calendar.　
D.　There　is　no　variation　in　using　the　American　language.　
03.　It　can　be　inferred　that　all　the　following　will　most　probably　be　included　in　the　seventy-three　items　except　____.　
A.　heir　and　heritage　
B.　childrearing　practices　
C.　dream　patterns　
D.　table　manners　
04.　By　saying　that　they　are　cultural　commas　and　semicolons...　the　author　means　that　commas　and　semicolons　____.　
A.　can　be　interpreted　as　subculture　of　American　life　
B.　can　be　identified　as　various　ways　of　American　life　
C.　stand　for　work　and　rest　in　American　life　
D.　are　preferred　in　writing　the　stories　concerning　American　life　
05.　The　authors　main　purpose　in　writing　this　passage　is　to　____.　
A.　prove　that　different　people　have　different　definitions　of　culture　
B.　inform　that　variations　exist　as　far　as　a　culture　is　concerned　
C.　indicate　that　culture　is　closely　connected　with　social　classes　
D.　show　that　the　idea　that　the　poor　constitute　a　separate　culture　is　an　absurdity　

Questions　06-10　are　based　on　the　following　passage:　

It　is　3A.M.　Everything　on　the　university　campus　seems　ghostlike　in　the　quiet,　misty　darkness　-　everything　except　the　computer　center.　Here,　twenty　students　rumpled　and　bleary-eyed,　sit　transfixed　at　their　consoles,　tapping　away　on　the　terminal　keys.　With　eyes　glued　to　the　video　screen,　they　tap　on　for　hours.　For　the　rest　of　the　world,　it　might　be　the　middle　of　the　night,　but　here　time　does　not　exist.　This　is　a　world　unto　itself.　These　young　computer　hackers　are　pursuing　a　kind　of　compulsion,　a　drive　so　consuming　it　overshadows　nearly　every　other　part　of　their　lives　and　forms　the　focal　point　of　their　existence.　They　are　compulsive　computer　programmers.　Some　of　these　students　have　been　at　the　console　for　thirty　hours　or　more　without　a　break　for　meals　or　sleep.　Some　have　fallen　asleep　on　sofas　and　lounge　chairs　in　the　computer　center,　trying　to　catch　a　few　winks　but　loathe　to　get　too　far　away　from　their　beloved　machines.　


Most　of　these　students　dont　have　to　be　at　the　computer　center　in　the　middle　of　the　night.　They　arent　working　on　assignments.　They　are　there　because　they　want　to　be　-　they　are　irresistibly　drawn　there.　


And　they　are　not　alone.　There　are　hackers　at　computer　centers　all　across　the　country.　In　their　extreme　form,　they　focus　on　nothing　else.　They　flunk　out　of　school　and　lose　contact　with　friends;　they　might　have　difficulty　finding　jobs,　choosing　instead　to　wander　from　one　computer　center　to　another.　They　may　even　forgo　personal　hygiene.　


I　remember　one　hacker.　We　literally　had　to　carry　him　off　his　chair　to　feed　him　and　put　him　to　sleep.　We　really　feared　for　his　health,　says　a　computer　science　professor　at　MIT.　


Computer　science　teachers　are　now　more　aware　of　the　implications　of　this　hacker　phenomenon　and　are　on　the　lookout　for　potential　hackers　and　cases　of　computer　addiction　that　are　already　severe.　They　know　that　the　case　of　the　hackers　is　not　just　the　story　of　one　persons　relationship　with　a　machine.　It　is　the　story　of　a　societys　relationship　to　the　so-called　thinking　machines,　which　are　becoming　almost　ubiquitous.　


06.　We　can　learn　from　the　passage　that　those　at　the　computer　center　in　the　middle　of　the　night　are　____.　
A.　students　working　on　a　program　
B.　students　using　computers　to　amuse　themselves　
C.　hard-working　computer　science　majors　
D.　students　deeply　fascinated　by　the　computer　
07.　Which　of　the　following　is　NOT　true　of　those　young　computer　hackers?
A.　Most　of　them　are　top　students　majoring　in　computer　programming.　
B.　For　them,　computer　programming　is　the　sole　purpose　for　their　life.　
C.　They　can　stay　with　the　computer　at　the　center　for　nearly　three　days　on　end.　
D.　Their　love　for　the　computer　is　so　deep　that　they　want　to　be　near　their　machines　even　when　they　sleep.　
08.　It　can　be　reasonably　inferred　from　the　passage　that　____.　
A.　the　hacker　phenomenon　exists　only　at　university　computer　centers　
B.　university　computer　centers　are　open　to　almost　everyone　
C.　university　computer　centers　are　expecting　outstanding　programmers　out　of　the　hackers　
D.　the　hacker　phenomenon　is　partly　attributable　to　the　deficiency　of　the　computer　centers　
09.　The　authors　attitude　towards　the　hacker　phenomenon　can　be　described　as　____.　
A.　affirmative　
B.　contemptuous　
C.　anxious　
D.　disgusted　
10.　Which　of　the　following　may　be　a　most　appropriate　title　for　the　passage?　
A.　The　Charm　of　Computer　Science　
B.　A　New　Type　of　Electronic　Toys　
C.　Compulsive　Computer　Programmers　
D.　Computer　Addicts　

Questions　11-15　are　based　on　the　following　passage:　
　　　Every　profession　or　trade,　every　art,　and　every　science　has　its　technical　vocabulary.　Different　occupations,　however,　differ　widely　in　the　character　of　their　special　vocabularies.　In　trades　and　handicrafts,　and　other　vocations,　like　farming　and　fishery,　that　have　occupied　great　numbers　of　men　from　remote　times,　the　technical　vocabulary,　is　very　old.　It　consists　largely　of　native　words,　or　of　borrowed　words　that　have　worked　themselves　into　the　very　fibre　of　our　language.　Hence,　though　highly　technical　in　many　particulars,　these　vocabularies　are　more　familiar　in　sound,　and　more　generally　understood,　than　most　other　technicalities.　The　special　dialects　of　law,　medicine,　divinity,　and　philosophy　have　also,　in　their　older　strata,　become　pretty　familiar　to　cultivated　persons　and　have　contributed　much　to　the　popular　vocabulary.　Yet　every　vocation　still　possesses　a　large　body　of　technical　terms　that　remain　essentially　foreign,　even　to　educated　speech.　And　the　proportion　has　been　much　increased　in　the　last　fifty　years,　particularly　in　the　various　departments　of　natural　and　political　science　and　in　the　mechanic　arts.　Here　new　terms　are　coined　with　the　greatest　freedom,　and　abandoned　with　indifference　when　they　have　served　their　turn.　Most　of　the　new　coinages　are　confined　to　special　discussions,　and　seldom　get　into　general　literature　or　conversation.　Yet　no　profession　is　nowadays,　as　all　professions　once　were,　a　close　guild.　The　lawyer,　the　physician,　the　man　of　science,　the　divine,　associated　freely　with　his　fellow-creatures,　and　does　not　meet　them　in　a　merely　professional　way.　Furthermore,　what　is　called　popular　science　makes　everybody　acquainted　with　modern　views　and　recent　discoveries.　Any　important　experiment,　though　made　in　a　remote　or　provincial　laboratory,　is　at　once　reported　in　the　newspapers,　and　everybody　is　soon　talking　about　it　-　as　in　the　case　of　the　Roentgen　rays　and　wireless　telegraphy.　Thus　our　common　speech　is　always　taking　up　new　technical　terms　and　making　them　commonplace.　
11.　Special　words　used　in　technical　discussion　____.　
A.　never　last　long　
B.　are　considered　artificial　language　speech　
C.　should　be　confined　to　scientific　fields　
D.　may　become　part　of　common　speech　
12.　It　is　true　that　____.　
A.　an　educated　person　would　be　expected　to　know　most　technical　terms　
B.　everyone　is　interested　in　scientific　findings　
C.　the　average　man　often　uses　in　his　own　vocabulary　what　was　once　technical　language　not　meant　for　him　
D.　various　professions　and　occupations　often　interchange　their　dialects　and　jargons　
13.　In　recent　years,　there　has　been　a　marked　increase　in　the　number　of　technical　terms　in　the　terminology　of　
A.　farming　
B.　sports　
C.　government　
D.　fishery　
14.　The　writer　of　the　article　was,　no　doubt　____.　
A.　a　linguist　
B.　an　essayist　
C.　a　scientist　
D.　an　attorney　
15.　The　authors　main　purpose　in　the　passage　is　to　____.　
A.　describe　a　phenomenon　
B.　be　entertaining　
C.　argue　a　belief　
D.　propose　a　solution　

Questions　16-20　are　based　on　the　following　passage:

In　the　days　immediately　following　hurricane　Andrews　deadly　visit　to　South　Florida,　Allstate　Insurance　hastily　dispatched　more　than　2,000　extra　claim　adjusters　to　the　devastated　area　to　assist　the　200　stationed　there.　Many　of　the　reserves　arrived　in　convoys　of　motor　homes.　Others　flew　in　from　as　far　away　as　Alaska　and　California.　Since　the　storm　had　knocked　out　telephone　lines,　Allstate　rushed　to　set　up　its　own　communications　system.　Allatate　expects　to　pay　out　1.2　billion　to　cover　more　than　121,000　damage　claims　as　a　result　of　Andrew.　


All　told,　U.S.　property　and　casualty　insurers　have　been　hit　with　more　than　8　billion　in　Andrew-related　claims,　making　the　hurricane　the　most　costly　single　calamity　to　strike　the　industry　since　the　San　Francisco　earthquake　and　fire　in　1906　(cost:　6　billion,　after　inflation).　With　claims　continuing　to　pour　in,　Andrew　threatens　to　take　a　painful　toll　on　the　already　battered　property-casualty　insurance　industry　and　its　100　million　policy-holders.　The　final　bill,　analysts　predict,　is　likely　to　top　10　billion.　While　most　well-capitalized　insurers　are　expected　to　weather　the　storm,　less　anchored　firms　are　in　danger　of　being　blown　away,　leaving　U.S.　consumers　stuck　with　the　tab.　Says　Sean　Mooney,　senior　researcher　at　the　Insurance　Information　Institute:　It　will　take　years　before　the　industry　digs　itself　out　from　the　wreckage　left　by　Andrew.　Some　[companies]　will　be　buried　by　it.　


Hurricane　Andrew　is　the　latest　in　a　string　of　mishaps　to　plague　the　American　insurance　industry　this　year.　In　April　an　overflowing　Chicago　River　flooded　the　citys　downtown　district,　costing　insurers　300　million　in　claims.　A　month　later,　Los　Angeles　was　rocked　by　the　worst　civilian　riot　in　the　U.S.　since　the　Civil　War.　The　insurance　toll:　1　billion.　Then　came　a　series　of　major　hailstorms　in　Texas,　Florida　an　Kansas.　They　cost　insurers　a　combined　700　million.　And　two　weeks　after　Andrew,　another　lethal　hurricane,　Iniki,　smashed　into　Hawaii,　causing　1.4　billion　in　damages.　In　all,　property　and　casualty　insurers　have　paid　out　a　record　13　billion　in　claims　so　far　this　year,　far　surpassing　the　previous　high　of　7.6　billion　in　1989,　the　year　of　Hurricane　Hugo　and　Californias　Bay　Area　earthquake.　Just　as　in　that　year,　when　those　catastrophes　were　followed　by　substantial　increases　in　insurance　premiums,　insurers　are　already　lobbying　for　rate　relief.　


16.　According　to　the　passage,　Allstate　Insurance　most　likely　refers　to　____.　
A.　one　of　the　property　and　casualty　insurers　in　the　U.S.　
B.　the　only　insurance　company　responsible　for　the　damage　claims　by　Andrew　
C.　the　insurance　industry　as　a　whole　
D.　the　biggest　insurance　company　in　the　U.S.　
17.　As　is　stated　in　the　second　paragraph,　the　result　of　Hurricane　Andrew　is　likely　to　____.　
A.　lead　to　inflation　throughout　the　U.S.　
B.　make　the　largest　insurers　suffer　the　most　
C.　put　the　industry　in　Sough　Florida　out　of　action　
D.　cause　insurers　with　insufficient　funds　to　go　bankrupt　
18.　Using　context　clues,　we　may　infer　that　stuck　with　the　tab　most　probably　means　____.　
A.　caught　in　the　hurricane　
B.　exposed　to　natural　disasters　
C.　trapped　in　financial　difficulties　
D.　extremely　vulnerable　to　further　damages　
19.　The　end　of　the　passage　implies　that,　to　compensate　for　their　huge　loss,　the　insurers　will　____.　
A.　resort　to　a　very　big　increase　in　insurance　premiums　
B.　ask　for　subsidies　from　the　federal　government　
C.　reduce　their　insurance　coverage　thereafter　
D.　require　a　higher　interest　rate　from　the　bank　
20.　The　main　purpose　of　the　passage　is　to　____.　
A.　show　the　severe　damages　and　heavy　losses　caused　by　Hurricane　Andrew　
B.　suggest　that　U.S.　insurers　are　virtually　unable　to　cover　the　damage　claims　any　more　
C.　tell　about　the　difficult　situation　faced　by　the　insurers　throughout　the　U.S.　
D.　prove　that　disasters　tend　to　cause　ever　worsening　devastation　as　time　goes　on　
　　
Part　II　Vocabulary　and　Structures　
　　
21.　For　Soviets,　clothing　is　the　____　of　greatest　complaint,　housing　follows,　and　food　is　last.　
A.　source　
B.　problem　
C.　cause　
D.　reason　
22.　As　a　student　of　Chinese　literature,　she　enjoys　giving　____　of　poems　by　her　favourite　poets.　
A.　recreations　
B.　recitations　
C.　repetitions　
D.　rehearsals　
23.　Professor　Allington　asks　his　students　to　read　the　newspapers　to　keep　____　of　current　events.　
A.　watch　
B.　observation　
C.　track　
D.　information　
24.　More　waste　materials　have　to　be　____　of,　which　cause　pollution　of　the　land,　sea　and　air.　
A.　detached　
B.　deserted　
C.　dismissed　
D.　disposed　
25.　Fred　was　____　in　the　alley　last　night,　and　all　his　money　was　taken　away.　
A.　held　back　
B.　held　up　
C.　held　off　
D.　held　on　
26.　The　doctor　carefully　examined　the　driver　who　suffered　____　all　over　his　body　in　a　car　accident.　
A.　scars　
B.　scratches　
C.　bruises　
D.　wrenches　
27.　Since　a　circle　has　no　beginning　or　end,　the　wedding　ring　is　a　symbol　of　____.　
A.　constant　
B.　infinite　
C.　prolonged　
D.　eternal　
28.　Dick,　who　had　failed　the　Maths　test,　was　sitting　on　a　bench　in　the　corner,　____　over　his　disappointment.　
A.　brooding　
B.　apologizing　
C.　meditating　
D.　complaining　
29.　It　is　hard　for　us　to　realize　what　____　lives　men　led　in　the　Middle　Ages.　
A.　grave　
B.　grim　
C.　greedy　
D.　gross　
30.　Recent　psychological　studies　have　shown　that　many　children　develop　fears　of　____　dangers.　
A.　imagination　
B.　imaginary　
C.　imaginable　
D.　imaginative　
31.　In　the　garden　bees　moved,　humming　thoughtfully,　from　____　flowers　to　purple　ones.　
A.　colourful　
B.　prosperous　
C.　scarlet　
D.　brilliant　
32.　At　last　I　____　the　article　that　I　had　been　looking　for　in　the　University　library.　
A.　ran　down　
B.　run　into　
C.　run　out　
D.　run　off　
33.　The　police　officer　assures　us　____　will　be　taken　to　guard　against　the　recurrence　of　such　incidents.　
A.　prevention　
B.　prediction　
C.　preparation　
D.　precaution　
34.　They　____　on　a　cure　for　tuberculous　while　they　were　doing　research　on　something　else.　
A.　founded　
B.　stumbled　
C.　fumbled　
D.　tripped　
35.　In　the　darkness,　Mrs.　Warren　____　her　way　into　the　kitchen　and　switched　on　the　light.　
A.　gripped　
B.　groped　
C.　guided　
D.　guarded　
36.　The　mother　separated　the　quarrelling　children,　and　gave　each　of　them　a　sharp　____.　
A.　punch　
B.　puppy　
C.　pinch　
D.　pumpkin　
37.　Last　week　the　seamens　strike　led　to　the　____　closure　of　the　whole　vast　dock　area.　
A.　virtual　
B.　factual　
C.　local　
D.　actual　
38.　George　Gallop　has　brought　all　his　polling　strategies　together　to　____　and　analyze　what　he　calls　future　force.　
A.　synthesize　
B.　standardize　
C.　identify　
D.　demonstrate　
39.　I　prefer　badminton　to　squash　tennis.　Its　not　so　tiring　____.　
A.　to　tell　the　truth　
B.　to　be　frank　with　you　
C.　for　instance　
D.　for　one　thing　
40.　You　will　find　it　worthwhile　to　keep　____　good　terms　with　the　supervisor　of　your　department.　
A.　at　
B.　in　
C.　on　
D.　to　
41.　Soccer　is　the　most　truly　international　team　sport,　but　there　is　still　some　question　____　whether　it　should　be　called　a　game　or　open　warfare.　
A.　due　to　
B.　as　to　
C.　in　addition　to　
D.　owing　to　
42.　Scarcely　____　now　without　some　sort　of　incident　involving　the　old　lady.　
A.　a　day　passes　
B.　passes　a　day　
C.　does　a　day　pass　
D.　has　a　day　passed　
43.　If　the　dog　hadnt　barked　loudly,　we　____　caught　red-handed.　
A.　wont　have　been　
B.　neednt　have　been　
C.　mustnt　have　been　
D.　shouldnt　have　been　
44.　Its　____　Ive　bought　plenty　of　money:　its　more　expensive　than　I　expected.　
A.　just　as　well　
B.　rather　
C.　may　as　well　
D.　preferred　
45.　____,　but　I　still　like　him.　
A.　Selfish　though　he　is　
B.　Selfish　as　he　is　
C.　Selfish　he　may　be　
D.　Whether　he　is　selfish　or　not　
46.　____,　Chinas　large　and　medium-sized　state　enterprises　need　to　improve　their　management　right　now.　
A.　As　it　should　be　
B.　As　it　must　be　
C.　As　it　is　
D.　As　it　were　
47.　He　worked　seven　days　a　week,　and　six　of　____　until　one　oclock　at　night.　
A.　that　
B.　those　
C.　which　
D.　them　
48.　The　suspicion　that　the　servant　is　dishonest　has　proved　____　true.　
A.　all　too　
B.　too　all　
C.　much　too　
D.　too　much　
49.　The　budget　they　made　is　unrealistic　____　it　disregards　increased　costs.　
A.　for　that　
B.　for　which　
C.　in　that　
D.　in　which　
50.　The　newly　developing　science　of　artificial　intelligence　aims　at　programming　the　computer　to　think,　reason　and　react　____　people　do.　
A.　by　the　same　way　as　
B.　in　much　the　same　way　that　
C.　with　the　same　way　as　
D.　as　much　as　the　same　way　that　

Part　III　Error　Correction　

Some　people,　in　all　seriousness,　say　that　humans　will　be　living　in　space　within　the　next　hundred　or　so　years.　Planet　Earth　will　be　crowded,　dirty　and　lack　of　resources.　A　sort　of　exodus　[51]　of　mankind　will　begin.　


Spaceships　will　be　assembled　so　that　they　revolve　around　the　earth.　Some　may　orbit　around　Mars.　These　space　stations　will　be　serviced　by　space　buses.　We　saw　the　first　space　bus　launch　in　[52]　April　1981.　This　was　Columbia,　it　made　several　[53]　orbits　around　the　earth　and　then　returned,　landing　on　a　huge　dry　lake　bed　in　California.　Columbia　will　be　used　again.　Previous　spaceships　have　been　abandoned,　only　the　nose　being　used　to　bring　the　crews　back　to　earth.[54]　


Upon　established,　each　space　station　will　[55]　generate　its　own　atmosphere　and　have　its　own　agriculture.　It　will　need　to　rotation　to　provide　[56]　an　artificial　gravity;　people　will　be　forced　inwards　[57]　from　the　centre　by　centrifugal　force.　


The　moon　and　Mars　could　become　new　sources　of　new　materials.　Driving　through　space　will　no　[58]　longer　need　Earth　fuel　-　the　energy　would　come　from　the　sun.　This　energy　would　be　converted　from　[59]　electricity　to　work　magnetic　rockets.　


That　all　sounds　quite　fantastically　but,　with　[60]　the　rapid　development　of　modern　technology,　who　knows　about　what　the　future　holds?　


答案
Part　I　Reading　Comprehension　
01.C　02.D　03.C　04.A　05.D　06.D　07.A　08.B　09.C　10.D　
11.D　12.C　13.C　14.A　15.A　16.A　17.D　18.C　19.A　20.C　

Part　II　Vocabulary　and　Structure　
21.A　22.B　23.C　24.D　25.B　26.C　27.D　28.A　29.B　30.B　
31.C　32.A　33.D　34.B　35.B　36.C　37.A　38.C　39.D　40.C　
41.B　42.A　43.D　44.A　45.C　46.C　47.D　48.A　49.C　50.B　

Part　III　Error　Correction　
51.　and　lack　of...　short　
52.　bus　launch　in...　launched　
53.　it　made　several...　which　
54.　the　crews　back...　crew　
55.　Upon　established...　once　
56.　to　rotation　to...　rotate　
57.　forced　inwards...　outwards　
58.　space　will　no...　would　
59.　converted　from...　into　
60.　quite　fantastically　but...　fantastic