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八年级下册语文书（人教版）封面下面的图片是哪一首诗的画 若3x+4y=a和4x+3y=5的解满足x,y为非负数,则a是否存在?为多少? 是否存在一个整数a,使方程组①4x+4y=a,②4x+3y=5的解是一对非负数?若不存在,请说明理由；若存在,求出个整数,并解方程组. 谁有初二下册（八年级下册）人教版的英语听力?有的请发送我的邮箱yuzhiq1@163.com 七年级上册语文课本上要被的诗文有哪些? 根据上下文的提示,给对话填上所缺的单词,每个空格只填一个单词.Mother:Today is Grandma's ______.Let's go shopping now.Son:Oh.great!Let's buy a bing birthday cake _____ Grandma.Mother:Yes.Buy a big ________.Son:Is it expensive, I'm going to write some articles and( )them to magazines and newspaper.A.send B.take C.bring D.giveI like the red silk scarves,but I don't like the black( )(one)我认为是ones...Some students are not( )enough while doing their homework ,so it takes ..,.今晚要用.翻译.1.听到你病了,我很伤心.I'm ____ _____ _____ you're _______. 六年级英语题..急.帮帮忙..今晚要用.一、不定项选择.1、Thank you very much.( ) A.Not at alll. B.You're welcome.C.That's all right. D.That's right. E.It's my pleasure. F.it doesn't matter.2.The apple tastes ____________( 已知二元一次方程4x+3y=-20,请用含X的代数式表示Y,Y=( ),写出方程的负整数解为（ ） 铜是和硝酸先反应还是和硫酸,为什么? 硫酸加硝酸和铜,反应生成什么? 一道定语从句英语题Was it in this house_____was built by the father_____his first daughter was born?A which ；where B that；which C that；what D which；that是选D 额 为什么呢? 关于定语从句的一道英语题The house where I lived ten years ago has been pulled down.这句话可以写成The house that I lived ten years ago has been pulled down.为什么?定语从句中怎么确定句子是用关系代词还是关系副 问个高1的英语定语从句题The film brought the hours back to me_____I was taken good care of that faraway village.A.until B.that C.when D.where 帮忙说下先行词 2(3y-3)=6x+4把改方程写成用含x的代数式表示y的形式 把下列方程写成用含y的代数式表示x的形式,并求方程的正整数解（1） x+3y=7 (2) 4x+3y=32 牛汉在语文课本中出现过的诗有哪些? 有没有关于牛汉的诗? 请问谁知道牛汉的一首诗叫 根 牛汉的小诗 一道定语从句的英语题You can borrow any book ____?A.that you interest B.you are interestedC.that interests you D.interests you 1.一个质量为60千克的人,在地球上的重力为588N,在月球上的重力为98N.此人做摸高运动时,在地球上的触摸高度为2.5米,若起跳速度相同,在月球上的触摸高度为多少?2.在一根弹簧下端悬挂重15N的 2道英语题目谢谢大家!在线等无论做什么事,都要尽力做好._____ you do , ___ your best___do it _____.走的时候务必把们锁上 _____ ____ _____ lock the door when you ____. （2道）.根据提示完成句子.1.What's the _______(day)?同义句转换.2.She lends me her pen.I _______ a pen from her.要求正确呢.求 2道英语题目 谢谢大家了1.根据首字母填空you are s__ to say so. Jim is ___A.six-year-old B.a six -years-old boyC.six-year-olds C.six years old 方程x-3y=1-x/2写成用含y的代数式表示x的形式是 稀硝酸与铜离子方程式 小华和小星两人站在地面上,小伟乘坐在沿水平方向匀速飞行的飞机上,某时刻小伟自由释放了一个玩具,若不考虑空气阻力,其中小伟观察到物体竖直下落的现象是以（ ）A.地面为参照物 B.飞机 （请说明理由）请解释hope用法与 help及make用法 请说明理由Do you know our town at all?No,this is the first time I ___here.A.wasB.have beenC.cameD.am coming 请说明理由为什么这样做1._____ can grow heathily without water or air.A.Everything B.Something C.Anything D.Nothing2.I don't think swimming is _______ hiking.A.not more exciting than B.so exciting as C.as interesting than D.more interesting