声音传播的三大途径

why did she fail the exam 等於why did not she pass the exam 几道生物填空题, 四个生物填空题,第1和3小题, 英译汉That's just fun with them.That's just fun with them. About 75% students say that their timetables during the school year are just right,but they don't make them happy. 会的请尽快举手已知x1,x2,x3的平均数为5，y1,y2,y3的平均数为7，则2x1+3y1,2x2+3y2,2x3+3y3的平均数为（）A.31 B.31/3 C.93/5 D.17 Mother's Day began in 1908 对这句话提问 强调句:what is it that makes them so unhappy? 这个是强调句?是不是强调句的疑问句?怎么辨别?谢谢! What is right for kids?完形填空的答案 Bamboo is hollow,____ makes them very light.A.that B.it C.what D.which讲清楚原因! 一个圆锥的体积是18立方米,和他等低等高的圆柱体积是【】立方米 What are the kids doing now?(on sunday)用所给时间改写句子. why do some people become alcoholics how can they solve their drinking problems? so they can’t understand why the doctor do some things这句话语法错误在哪?我想表达的意思是 所以他们不能理解医生为什么做有些事 .网站评定说这句话有语法错误 many children serve their mothers breakfast in bed.这句话中serve是什么意思啊（准备好、、、端上、、、扶起、、、喂食） 一道英语填空题, 为什么是have breakfast in bed而不是in the bed?When Linda was a child,her mother always let her have breakfast ____?A.in the bed B.in bed为什么答案是in bed而不是in the bed?in bed不是“（生病）卧床”的意思吗? 一道英语填空题, Breakfast In Bed 歌词 BED BREAKFAST怎么样 For those that are still possible I am sensible that a good deal more is still to be done 怎么翻译 It was order that tickets _ given free to those lacking money to buy them.A.were B.have been C.be D.are 英语翻译An earthquake is a phenomenon that results from and is powered by the sudden release of stored energy in the crust that propagates seismic waves.At the Earth's surface,earthquakes may manifest themselves by a shaking or displacement of th 猫科动物最凶猛的是哪个老虎除外 猫科动物一般都很凶吗 二十种最凶猛的猫科动物 作文南京大屠杀读后感 蚊子的自述600字左右说名文 雨的自述600字 电子吊秤都有哪些种类,它们的优点和缺点是什么 请帮我修改一下我写得这一小段话,或给我添加点东西也行.添加多点东西,我这段话文字太少了,总之让它变得更好就可以啦:人为什么活着?为了自己的梦想而活,而在不屑追求梦想的过程,便叫 修改一小段话If the qualified translators want to translate the attributive clause smoothly and successfully,not only knowing the method is not enough,but also improving the compression level,improving the other practice abilities,including lang