Inspring,chickensstartlayingagain,bringingawelcomesourceofproteinatwinter’send.Soit’snosurprisethatculturesaroundtheworldcelebratespringbyhonoringtheegg.Sometraditionsaresimple,liketheredeggsthatgetbakedintoGreekEasterbreads.Otherselevatetheeggintoafancyart,liketheheavilyjewel-covered“eggs”thatwerefavoredbytheRussiansstartinginthe19thcentury.OneancientformofeggartcomestousfromUkraine.Forcenturies,Ukrainianshavebeendrawingcomplicatedpatternsoneggs.Contemporaryartistshavefollowedthistraditiontocreateeggsthatspeaktotheanxietiesofourage:Lifeisprecious,anddelicate.Eggsare,too.“There’ssomethingabouttheirdelicatenaturethatappealstome,”saysNewYorkercartoonistRozChast.Severalyearsago,shebecameinterestedineggsandlearnedthetraditionalUkrainiantechniquetodrawherverymodemcharacters.“I’vebrokeneggsateverystageoftheprocess—fromtheverybeginningtothevery,veryend.”Butthere’sanappealinthatvulnerability.“There’spartofthissickeninghorrorofknowingyou’rewalkingontheedgewiththis,thatIkindoflike,knowingthatitcouldallfallapartatanysecond.”Chast’sdesigns,suchasaworriedmanaloneinatinyrowboat,reflectthatdelicateness.TraditionalUkrainiandecoratedeggsalsospoketothosefears.Theelaboratepatternswerebelievedtoofferprotectionagainstevil.“There’sanancientlegendthataslongastheseeggsaremade,evilwillnotprevailintheworld,”saysJoanBrander,aCanadianegg-painterwhohasbeenpaintingeggsforover60years,havinglearnedtheartfromherUkrainianrelatives.Thetradition,datingbackto300B.C.,waslaterincorporatedintotheChristianchurch.Theoldsymbols,however,stillendure.Adecoratedeggwithabirdonit,giventoayoungmarriedcouple,isawishforchildren.Adecoratedeggthrownintothefieldwouldbeawishforagoodharvest.8.Whyhavecontemporaryartistscontinuedtheeggarttradition?

性反应周期中获得极度心理快感的时期是（）。

所谓“性反应”，其实也就是性欲的发动和满足的过程。简明的说法就是“积欲”和“解欲”。

四个阶段是一个连续的、不可分割的完整的性反应的动态过程，包括：平台期、兴奋期、高潮期、消退期。

前自慰行为对个体心理正常成长、对在性成熟时建立正常的性反射神经通路及性反应应该说是必须的途径之一。

女性只有多次性高潮，才是正常的反应。

某项5年期借款500万元，年利率为8%，若每半年复利一次，年实际利率比名义利率多（）

关于卤化反应的不饱和烃卤加成的影响因素，下列说法正确的是

关于不饱和烃的卤加成反应的机理，说法正确的是

药物合成反应的主要目标

关于饱和脂肪烃上的卤取代反应，说法正确的是

羧酸和草酰氯的反应，下列正确的为

关于不饱和烃的卤加成反应，说法正确的是

酮的α-卤取代反应的应用是

关于醇和氢卤酸的反应，下列说法正确的是