Peopleinthepastmadeclay-potterybecausetheyneededitfortheirlives.Theyusedthepotstheymadeforcookingstoringfoodandcarryingthingsfromplacetoplace.Potterywassoimportanttotheearlyculturethatscientistsnowstudyittoleammoreaboutancientcivilizations.Themoreadvancedthepotteryintermsofpicturesmaterialsandmakingthemoreadvancedthecultureitself.

TheartisanwhomakespotteryinNorthAmericatodayusehisorherskillandimaginationtocreateitemsthatarebeautifulaswellasusefulturningsomethingordinaryintosomethingspecial.ThepotterusesoneoftheEarth'smostbasicmaterialsclay.Claycanbefoundalmostanywhere.Goodpotteryclaymustbefreefromallsmallstonesandotherhardmaterialsthatwouldmakethepottingsteps

difficult.MostNorthAmericanartisanpottersnowbuyready-madeclayinstoresbutsomefindtheclaytheyneedrightintheearthclosetowheretheywork.

Themostimportanttoolspottersusearetheirownhands;howevertheyalsousewoodenmodelingtoolsplainwireandsponges.Plainwireisusedtocutawaythefinishedpotfromitsvaseonthepotter'swheel.

Afterafinishedpotisdriedofallitswetpartintheopenairitisplacedinakilnandfired.Thefirstfiringhardensthepotteryariditisthenreadytobeglazedandfiredagain.

Forareaswheretheydonotwantanyglazesuchasthebottomofthepotartisanspaintonmeltedwaxthatwilllaterbumoffinthekiln.Theythenpourontheliquidglazeandletitrunovertheclaysurfacemakinganykindofdesignsthattheywant.

41.Whatdoesthepassagemainlydiscuss?

A.Differentkindsofclay　B.Thetrainingofanartisan

C.ThemakingofpotteryD.Thelivesofpeopleinthepast

42.Theword"it"inparagraph1refersto.

A.clay　B.pottery　C.livesD.culture

43.AccordingtothepassagehowdomostNorthAmericanpotterstodaygettheclaytheyneed?

A.Theybuyit.B.Theymakeit.

C.Theydigitfromtheearth.　D.Theyexchangeforit.

44.Accordingtotheauthorwhatdopottersusetoremovethepotfromthewheel?

　A.MeltedwaxB.Aplainwire　C.pottersownfingers　D.fire

45WhichmaterialisNOTusedintheprocessofmakin