on在某物的上面.但两者互相接触.如: The map of China is on the wall. 查看更多

 

题目列表(包括答案和解析)

某同学探究平面镜成像时,将一块玻璃板竖直架在一把直尺的上面,再取两段等长的蜡烛A和B一前一后竖放在直尺上,点燃玻璃板前的蜡烛A,用眼睛进行观察,如图所示。在此实验中:

  (1)直尺的作用是           
  (2)两段等长的蜡烛作用是_______________;
  (3)移去蜡烛B,并在其所在位置上放一光屏,则光屏上     
(4)接收到蜡烛A的烛焰的像(填“能”或“不能”).这说明平面
镜成的是      像。

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如图14所示是探究平面镜成像特点的实验装置图。将一块玻璃板竖直架在一把刻度尺的上面,并保持玻璃板与刻度尺垂直。再取两根完全相同的蜡烛A和B分别竖直置于玻璃板两侧的刻度尺上,点燃玻璃板前的蜡烛A,进行观察和调整。用此实验可以研究:①像与物大小的关系;②像与物到平面镜距离的关系;③平面镜成的是虚像还是实像。
(1)选用刻度尺的作用是为了便于比较_________;(选填“①”、“②”或“③”)
(2)选用两根完全相同的蜡烛是为了比较________;(选填“①”、“②”或“③”)
(3)在利用蜡烛B确定出蜡烛A所成像的位置后,移去蜡烛B,并在其所在位置上放一光屏,则光屏上_________(选填“能”或“不能”)接收到蜡烛A的像。

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Millie wants to solve the crime.She made some notes on the case in her diary, but she made 15 mistakes because she was sleepy.Help her correct the mistakes.Write the correct words above the mistakes.

米莉想要解决这起犯罪,她就这个案件在她的日记里作了记录。她犯了15处错误。帮她纠正错误,在错误单词的上面写出正确的单词。

  29th December

  Today, something terrible happened.(1)An old man was murdered in(2)NewTown.The body was found in the door way of a(3)medicine shop.The victim was a(4)policeman who worked in(5)Valley Town.When he left(6)home, he said he was going to visit his(7)cousin

  The murder took place between(8)  7  p. m. and 1 a. m.The victim was killed with a(9)gun and there was evidence of a(10)game.The police are looking for(11)scenes that will help us find the murderer.(12)A suspect saw a man(13)walking down Upper Street with blood on his(14)trousers.The man said that he had(15)someone to prove that he was not at the scence of the crime.

  十二月29日

  今天可怕的事发生了。在新城一位老人被杀了。尸体是在一家药店的门口被发现的。受害人是个在峡谷镇工作的警察。当他离家的时候,他说他要看望他的堂弟。

  案件发生在晚上7点到凌晨1点期间。受害人是被枪杀的,有搏斗的迹象。警察正在寻找有助于他们找到凶手的线索。

  一个嫌疑犯看见一个穿着带血的裤子的人沿着上街跑。这个人说他有人证明他不在犯罪现场。

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Talk about your abilities with your partners in English. (和你的同伴用英语谈论你们在某方面的能力)

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书面表达。
     假如你是Jack,Tom来信邀请你参加本周末在他家举办的聚会,但你因故不能参加,请你给Tom回信表示歉意,并根据所提示的内容说明原因。词数60~ 80。

                                                                                                                                                                 
                                                                                                                                                                 
                                                                                                                                                                 

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