一次特别的作业450字

计划赶不上变化是什么意思 石灰石磨粉机一般都有些型号?石灰石磨粉机价格标准是什么?石灰石磨粉机哪个牌子的好?如题,想了解一下价格水平及厂家情况. ．图2是某家庭电路,闭合开关S1、S2,L1 灯发光,L2 灯不发光.用试电笔分别接触c、d 两点,氖管都发光.图2是某家庭电路,闭合开关S1、S2,L1灯发光,L2灯不发光.用试电笔分别接触c、d两点,氖管都发光. 请问什么是“半马尔科夫过程” 请问什么是“半马尔科夫过程”--不是问“马尔科夫过程” 完全看不懂的…… 时间连续状态连续的马尔科夫过程都有哪些? 有一物体通过两个细线绳悬挂在小车的车顶上,小车在水平面上做直线运动.某时刻正处于右图所示状态.关于此时刻物体的受力情况,下列说法正确的是A.若小车向左运动,AC绳的拉力可能为零 B. （2009•龙岩模拟）如图所示,小车内有一固定光滑斜面,一个小球通过细绳与车顶相连,小车在水平面上做直线运动,细绳始终保持竖直．关于小球的受力情况,下列说法中正确的是（　　）A 请问：four years out of the last ten, scientists say that four years out of the last ten have been the hottest since records began 啥意思 four out of last seven Not until i reminded him for the third time did he stop working and looked up改成普通句子是这样么?he stoped working and looked up,until i reminded him for the third time He did not stoped working and looked up until i reminded him for the third time.中did后去试还用过 not until I remined him for the third time did he stop working and looked up.请问,为什么要用“looked up",因为这里后面要用倒装,所以这里的look感觉应该和stop一样,用原型啊,因为都是在did倒装结构之后的动作, He did it in one-third the time it took me.怎么翻译 sandy wants to visit china改为反义疑问句there is litter water in galss改为反义疑问句 在过去的十年里,人们的生活变化很大.（in the last ten years） ___________________________________ 这个短语到底用什么时态呀,in the last ten years in China,150million people moved out of poverty .可是一会又在同一教材中看到后面接的是现在完成时,真把我弄糊涂了 in the last ten years指在过去的十年里,be said to do 表示据说?He is said （ ）five trips to Beijing in the last ten years.A to make B to have made C to have been making D to be making如果是B,是不是过去完成时,只不过have放 I often dream of Paris,but I've never been there. It's the place____.A where I'd likeB that I want to visit it mostC in which I'd like to visitD I most want to visit I've never been to my parents' hometown,but it‘s the place______.A.in which I'd like to visit B.where I'd like to visit C.I want to visit most D.that I want to visit it most 为什么选c呢 in the last ten years 与in the past few years是不是只能用于完成时呀 什么单词发ear 有ear的词语 如图所示,小车内有一固定光滑斜面,一个小球通过细绳与车顶相连,小车在水平面上做直线运动,细绳始终保持竖直.关于小球的受力情况,下列说法正确的是[     ]A．若小车静止, 发电机为什么通入直流电建立磁场 我想利用磁生电做一个发电机,磁场怎么产生啊? 没有GGH的（FGD）石膏湿法脱硫烟囱衬里如何防腐目前哪种技术相对成熟 没写的!ggh you will more beautiful when you are 25 years old划线部分提问划线部分more beautiful___ will you be ___ when you are 25 years old 火车由静止开始以加速度α启动,由甲站出发随后再以加速度β运动而停止于乙站.设甲、乙两站间的距离为d.（1）由甲站到乙站共经历多少时间?（2）全程的平均速率为多少?（3）车速所能达到