精品英语资料Unit 3 FOOD AND CULTURE.docxVIP

Unit3FOODANDCULTURE

第二部分阅读理解（共两节，满分35分）

第一节（共10小题；每小题2.5分，满分25分）?

阅读下列短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

A

Spider(?蜘蛛)silkhaslongbeenknownforitsimpressivecharacteristics,suchasamazingtoughness.Nowresearchershavefoundaspecialkindofwebbingthatactsasbothaliquidandasolid.Whatsmore,theyvecreatedaman-madesilkthatcouldfinduseinsoftrobotics.

Researchersstudiedthesilkofanorb-weaverspider?—thestickysilkthatmakesupaspidersweb.Theyfoundthesilkcanbecomelongerwhenpulled,justasyouwouldexpectfromasolidmaterial.Butwhentheypressthesilktogether,theyfounditremainedtight,ratherthanbendinginthemiddleasanordinarypieceofthreadmight.

“Youcangoupto95percentanditremainstight,”saysArnaudAntkowiak,oneoftheresearchers.“Weknowofmaterialsthatbehavelikethis,butthesearenotsolids;theyareliquids.”Thesilkseemstoofferthebestofbothworlds,adaptingitssizetothespaceitneedstofill.

“Itsjustamazing,”saysAntkowiak.“Thesilkconsistsofthinthreaddecoratedbygluedroplets(液滴).Itsamaterialconsistingofliquidandsolid.”Asthesilkispressed,thethreadbuckles(扣紧)itselfinsidethedropletswhilekeepingthethreadtight.?

Theteamusedplasticthreadcoatedinsiliconeoil,ethanolorotherliquidstocreatewhattheycallliquidwires.“Wedidhundredsofexperimentswithdifferentmaterialsandliquids,”saysAntkowiak.“Wefoundthatwecouldbucklealmostanythreadsurroundedbyanydroplet.”

“Itopensupthepossibilityoffuturesuccessintheareasofsoftrobotics,microfabrication,andmoregenerallymaterialscience,”saysAntkowiak.

21.Whatdidtheresearchersfindoutabouttheorb-weaverspiderssilk?

A.Itcanbendinthemiddle.

B.Itisassoftasaliquidmaterial.

C.Itisthinnerthanordinarythread.

D.Ithasqualitiesofbothsolidsandliquids.

22.Howdidtheresearchersdeveloptheliquidwires?

A.Bycombini