下列哪种说法可以概括三种原子光谱的产生机理

He _______(read) the novel twice last year .He has _________ been to Shanghai ,has he?A already B.never C.ever D.still-_______you ________ your homework?-Yes I_________it a moment ago .A Did;do; finishedB Have;done;have finishedc Have done finished D he_______ (read) the novel twice Peter__the book twice since last year A.has read B.had read 选A还是B, my father has read the novel twice请问这句话在现在完成时范畴内表示的什么?是表结果,还是持续的动作? I______（read) the novel twice.It's interesting.（用适当的动词填空） 给我5个英语幽默故事,附加中文（50字内!）要4年纪的 英语小故事和英语诗歌和英语笑话3篇50字左右是10到20字 五分钟幽默哲理小故事 1：is that his pen?改复数 2：she is my good friend.改为一1：is that his pen?改复数2：she is my good friend.改为一般疑问句3：that is Cheng Long改一般疑问句4：it's dave.改一般疑问句 请问广州初一英语有什么语法内容?A、B册的都要,所有语法内容.我是问有什么语法点，例如冠词、定从什么的，答购书中心之类的不相干。 The installed version of Directx is not supported dy 永恒之塔出现了、The installed version of DirectX is not supported by Aion怎么解决、帮帮. 出现unable to find a version of the runtime to run this application.我的电脑出现打开文件,老是弹出Unable to find a version of the runtime to run this application.打不开文件.怎么办,我是小白!复制的别来.囧o(╯□╰)o. Directx has determined that a newer version of directx is already ins谢谢二楼的翻译，我想问的是电脑安装的是directX11，为什么安装directX9的游戏时会出现这个问题呢，最后游戏安装完了但是打不开。 Mismatch Directx version! 莫泊桑短篇小说精选读后感 莫泊桑短篇小说摘抄300字左右 读后感 莫泊桑短篇小说集的读后感怎么写?只要字数到500,内容丰富,不管是百度的,还是自己写的,但是百度上的最好改一下,多一点.a要文章,不要说什么自己想之类的话! 《莫泊桑短篇小说集》读后感 急. 比较级的最高级前加the的短语 短语的最高级前面加不加the?这几个单词：delicious/danger/beautiful 词组前不要加the吗best friend 翻译短语时名词前面何时加the 何时不加the? 英语短语前面要加the么?比如铅笔盒,电话号码...真的很急啊,快回答啊... 鸭叫声英语怎么说quack,quack 鸭柺 翻译成英语怎么说是一道菜名啊， 指的是鸭掌上面的一个部分，就是不知道怎么翻 sorry.this copy premiere has expired是什么意思 premiere pro cs4出现licensing for this product has expired怎么办 this evalusation version of deepfreeze has expired 求一首英文歌名?像布兰妮的声音有点像布兰妮的声音歌词有一段独白似乎是ever will for you so pasenly!i know you hear 然后啊了一会 you are my answer 否定祈使句的疑问句回答Don't forget to send him an e-mail on his birthday.的否定回答是,No,I_____?为什么 she is her good friend.（改为一般疑问句）