向量的协方差

英语 改同义句：i don not know how i can use commas改为i don not know （ ）（ ）（ ）commas My sister can join (the swimming club.) 对括号部My sister can join (the swimming club.) 对括号部分提问.____ ____ _____ you sister ____? My sister can join the art club.对join the art club提问 wanda rodriguez’s father leaves her when she is a kid. I drop into water打一个单词,大家不要想太多,不要翻译成中文猜 OF WHICH 和 WHOSE的区别?THE WHITE BUILDING,____THE ROOF WAS DAMAGED IN THE BIG FIRE LAST NIGHT, IS ACTUALLY A SMALL HOSPITAL.为什么填OF WHICH 呢?和WHOSE有啥区别啊? If we don't save water,the last drop of water would our tear drop" 根据问题写一篇英语作文不要原文哦提示1.生活离不开水源,2.可饮用水的数量减少3.水污染严重4 应该保护和再利用参考词汇：the amount of wate i don t know how ---(use) commas.i don t know how ---(make) with others.等一系列问题 怎么答啊要快啊、我就等到19. I don't know how commas 该是什么I dont't know how use commas 为什么选use to use there are five pairs ___,but I'm at a loss which to buy.a to be chosen b to choose from c to choose d for choosing为什么不用被动? The house has been added to(=new rooms,etc.have been built on to it) from time to time.本句括号中的解释语中new rooms,etc.have been built on意指“新房子等已被扩建”不就是完整的意思了吗?为什么后面还要加用to it, john has been to the usa a few times 改为一般疑问句 Remember not to play water or fire英语单句改错!Remember not to play water or fire错了,讲出原因~ what which在表语从句中的用法区别,要例句 将I am good at swimming.改成同义句是? 是'i am good at swim'还是'i am good at swimming'? I am good at swimming.改为同义句（大家快点哦） 连词成句Mike and the for Cathy policeman asked and went to help Let’s （）（sit）on the bench.Don’t （）（sit）on the grass. On me way,I saw a grand sit on a bench last day语法哪错了? Let's sit on the grass.改成现在进行时,如何改,谢谢! I will let him sit behind me on my bicycle. 连词成句：邮局离这里不远,你可以步行去那儿.is,far from,the post office,here,on foot,go there,can,you,not,当她听到这个消息后,她的眼里充满了泪水.hear,tears,full of,when,she,the news,get,her eyes.年轻的时候,迈 you can 【a.】 join the swimming club I____(feel) it absolutely necessary for me to make the preparation. There is like a holiday to make us feel relaxed.A.something B.anything C.nothing D.everything填答案的地方在like前 plenty of wish Yepp wish it's the end of the world 啥意思? 为什么英文的11、12是eleven、Twelve而不是oneteen、twoteen?很想知道原因! The post office is quiet far from here. 1.I have a pen pal in the United States和I have a pen pal from the United States哪个正确? Can the poor people have car in the United States?急