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我国劳动人民发现铁可以从某些含铜化合物的溶液中置换从来,是在? (1)Please do not e_____ before knocking on the door. This is a map of the United Kingdom or the U.K.帮忙划分一下主、系、表 结构! Teachers let me into the house,then followed himself in,closed the door.He looked with interest,怎么翻译 THE HOUSE WITH CLOSED SHUTTERS怎么样 The house with a white door is m______. this is my classroom.the waii are white这个句子 哪里错了 I don't see any point __ the question any further.A to discuss B in discussing C of discussing D discussed I don't think it is any use discussing this matter any further.中文是?It is no use/not any use/useless doing sth 这个意思是? 夏天用保温饭盒带饭中午吃会变质吗?在这个天气,早上把饭菜弄好,剩热放到保温饭盒里会坏吗.在中午的时候吃.我买了一个膳魔师的保温饭盒,但是最上面的菜是常温的,只有下面的汤盒和饭盒 Don't Look Any Further歌词谁有麻烦给我 英语句子改错:You don't have the correct point view on this question 为什么电泳保护器前要用一个断路器?这个断路器怎么选? 电涌保护器是漏电开关吗?有何区别 英语翻译英语翻译 英语翻译 求几句赞美山河的语句最好是名句. carry this bag which is the_____(light) of the three big,and,the,light,bag,is(.)连词成句 bag the is light but big 排序是不是少了and 澳大利亚中部有(南回归)线穿过,气候炎热,( )广布 we should never wait for the door to open before 物质溶解时,要吸收热量吗? 从1累加到20,用加权符号怎么表示? 关于累加符号老师好,累加符号 如果是"-1/2∑Ai " ,其中i = 1,2,...,n .是不是:- 1/2(A1)-1/2(A2)-1/2(A3)-...-1/2(An)呢? 关于累加符号的问题请问图片中的公式意思是：1.“P(fi)Xfi”乘积的累加还是2.“P(fi)”累加的和乘以“fi”? 八孔箫指法表指法与音调的关系我看了一下八孔箫指法表,同样的指法,为什么下面不同的调后面会有不同的音名,如：八孔全闭时,G调是5附点,D调是1附点,C调是2附点,F调是6附点,bB调是3附点.那 口罩要怎么起才好 糖溶解过程中释放能量吗和能量的流动有什么关系? My husband likes to sleep in summer with the door and windows ___?应该填什么单词为什么填这个单词? The old man was dead in the house,____All the windows____.A of ,close B with;closed Cthrough ;openD by opened 请问各位导师不锈钢为什么要用到氢气?用其它气体不行吗?还有用到氢气的那台机器是什么机器?氢气在不锈钢厂的用途？