简介:<正>妈妈和阿姨们都喜欢穿高跟鞋,可是走路多了就会很累,甚至脚疼。我想发明一种鞋跟能伸缩的鞋子,在鞋上不易碰到的地方安装一个开关。当你按动开关时,鞋跟就像照相机的伸缩镜头一样自动
简介:Directions:Readthefollowingpassage.Thepassageisfollowedbyseveralquestionsorunfinishedstatements.ForeachofthemtherearefourchoicesmarkedA,B,CandD.Choosetheonethatfitsbestaccordingtotheinformationgiveninthepassage.Healthykneesaren’tthemainconsiderationinchoosinghighheels,butnewresearchsayschunkyheelsarejustasbadforthekneesasspindlystilettos(细高跟鞋)."Ittakesalongtimetofeeltheeffectsofkneeosteoarthritis(骨关节炎)—andonceyoudoit,itistoolate,"saidDr.CaseyKerrigan,leadingresearcherofthestudyandassociateprofessoratHarvard