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Unit1 Where did you go on vacation词组

Unit1  Where did you go on vacation词组
Unit1  Where did you go on vacation词组

Unit1 Where did you go on vacation?

1. go on vacation 去度假

2.stay at home 待在家里

3.go with someone 同某人一起去

4. go somewhere interesting 去某个有趣的地方

5. take quite a few photos 照了不少照片

6. go to summer camp 去参加夏令营

8.buy something special for yourself 为你自己买特别的东西

9.keep a diary 写日记

10.most of the time 大部分时间

11. taste really good 尝起来很好吃

12. of course 当然

13.feel like 给……的感觉;感受到

14. enjoy walking around 喜欢四处走走

15. because of bad weather 因为坏天气

16. one bowl of… 一碗……

17. the next day 第二天

18. find out 找出;查明

19. in the past 在过去

20.arrive in penang in Malaysia 到达马来西亚的槟榔屿

21. decide to go to the beach near the hotel 决定去我们宾馆附近海滩

22.nothing…but+动词原形除了……之外什么都没有

23.seem+(to be)+ adj. 看起来……

24.wait over an hour for the train 等火车等了一个多小时

25. bring enough money 带足够多的钱

26. try paragliding 尝试滑翔伞运动

27. forget to bring an umbrella. 忘记带一把雨伞

28. start raining 开始下雨

29. walk another two hours 又走了两个小时

30.bring back something from Malaysia 从马来西亚带回一些东西

31.jump up and down in excitement 兴奋的上下跳跃

32.forget about the last five hours 忘记过去五小时

33.tell me to keep going 告诉我继续走

34.get to the top 到达山顶

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Unit 3 Under the sea 语言点 编稿:牛新阁审稿:王春霞 学习目标 重点词汇 annual witness accommodation opposite yell pause drag depth urge abandon target reflect scare awesome 重点短语 in the meantime be aware of ahead of ... to death help (...)out upside down 重点句型 It takes sb. some time/ ... to do sth.的变化 a time when... 知识讲解 重点词汇 annual 【原句回放】It was a time when the killer whales, or “killers” as they were then called, helped the whalers catch the baleen whales that were on their annual migration. 那个时期,虎鲸(当时被称为“杀手”)帮助捕鲸人在每年须鲸迁徙时捕捉须鲸。 【点拨】annual adj. 1. 每年的,一年一次的 the annual output 年产量an annual report 年度报告 Steel output reached an annual figure of one million tons. 钢的年产量达到100万吨。 2. 按年度计算的 the annual income 年收入the annual rainfall 【拓展】annually adv. 每年地,年度地 witness 【原句回放】I thought, at the time, that this was just a story but then I witnessed it with my own eyes many times. 当时我以为这只是一个故事罢了,但是后来我亲眼见过多次。 【点拨】witness vt.& vi.亲眼看见,目睹,作证; n.见证人;目击者(与of连用) We were witnessing the most important scientific development of the century. 我们正目睹着本世纪最重要的科学发展。 We witnessed great changes in the city. 我们见证了这个城市的巨大变化。 The police found the witness of the murder case. 警察找到了那起谋杀案的证人。 There was no witness at the scene of the accident. 在事故现场没有目击证人。 【拓展】常见搭配:witness to (doing...)为……作证 bear / give witness to 为......作证 in witness of 作为......的证据 a living witness to 活生生的证人 witness stand 证人席(美)=witness box (英) He witnessed to having seen the man enter the building.

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自然拼读词汇 一.a e i o u 的短音 Aa: a n a m a t f a t h a s a nd b a g c a p c a t h a t f a t s a d h a d r a n p a n c a n m a n b a ck th a t th a nk h a ppy st a nd bl a ck p a nda f a mily dr a gon a pple h a ve M a ths a nimal gr a ndma gr a ndpa bl a ckboard ban a na a pple p a rrot a nimal c a rry r a ng st a nd m a tter c a tch Ee: leg g e t b e d y e s r e d t e n h e lp h e llo d e sk s e ven el e ven tw e lve p e n p e ncil e lephant t e nnis pr e sent dr e ss w e st Ii: i s i t i n h i s s i x b i t c i ty th i s b i g sh i p th i n sk i p f i sh m i lk s i n g g i ve w i ndy an i mal sw i m d i nner w i nter an i mal b i scuit c h i ldren

chopst i cks d i ff i cult dr i nk dumpl i ng f i fteen f i fty h i ll k i d l i sten l i ttle l i ve p i cture P i nk s i xteen s i xty sw i m v i sit w i n w i nner s i t g i ve w i nd w i th sk i p m i ss ch i ck f i n i sh f i nger fam i ly s i ster pol i cemen Oo: o x o n o f n o t d o g o n h o t g o t b o x d o ll d o ctor b o dy s o ng p o p pr o ject st o p o range cl o ck fr o g fr o m l o st s o rry b o x h o t l o st dr o p cr o ss b o ttle c o ffee sh o pping Uu: u p b u s m u m b u mp l u nch s u mmer s u nny u nder r u n r u nning l u ck d u mpling h u ndred h u ngry j u mp j u mping m u ch m u m j u st h u rry

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( )1. A. gave B. giraffe C. garden ( )2. A. great B. rage C. large ( )3. A. guitar B. grapes C. page ( )4. A. tiger B. orange C. green ( )5. A. circus B. circle C. cent ( )6. A. cane B. cite C. camera ( )7. A. snake B. crab C. plate ( )8. A. beans B. head C. these ( )9. A. cage B. gray C. black ( )10. A. radio B. thirteen C. video ( )11. A. smile B. listen C. hire ( )12. A. boat B. sock C. loaf ( )13. A. crocodile B. yogurt C. goat ( )14. A. butter B. ruler C. puppet ( )15. A. rage B. giraffe C. guitar ( )16. A. circle B. cane C. cite ( )17. A. candy B. catch C. circus D. corn ( )18. A. page B. orange C. bag D. gate ( )19. A. girl B. good C. giraffe D. cabbage ( )20. A. crocodile B. goat C. yogurt ave B. plate C. crab ( )21. A. g ( )22. A. cane B. cite C. climb ( )23 A. hire B. listen C. smile ( )24. A. ruler B. butter C. puppet ( )25. A. Ann B. cat C. potato D. carrot ( )26. A. three B. these C. key D. pencil ( )27. A. listen B. crocodile C. fifteen D. litter ( )28. A. snake B. sorry C. zoo D. salad ( )29. A. fish B. five C. fifeen D. gift ( )30. A. jump B. lulu C. run D. butterfly ( )31. A. blue B. flute C. sun D. Sue ( )32. A. these B. bean C. insect D. tea ( )33. A. potato B. tomato C. bag ( )34. A. egg B. see C. fourteen ( )35. A. nut B. flute C. jump

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令单位加速度输入的稳态误差,利用上式,可得 试探法 采用试探法,首先仅选择比例校正,使系统闭环后满足稳定性指标。然后,在此基础上根据稳态误差要求加入适当参数的积分校正。积分校正的加入往往使系统稳定裕量和快速性下降,此时再加入适当参数的微分校正,保证系统的稳定性和快速性。以上过程通常需要循环试探几次,方能使系统闭环后达到理想的性能指标。 齐格勒-尼柯尔斯法 (Ziegler and Nichols ) 对于受控对象比较复杂、数学模型难以建立的情况,在系统的设计和调试过程中,可以考虑借助实验方法,采用齐格勒-尼柯尔斯法对PID调节器进行设计。用该方法系统实现所谓“四分之一衰减”响应(”quarter-decay”),即设计的调节器使系统闭环阶跃响应相临后一个周期的超调衰减为前一个周期的25%左右。 当开环受控对象阶跃响应没有超调,其响应曲线有如下图的S形状时,采用齐格勒-尼柯尔斯第一法设定PID参数。对单位阶跃响应曲线上斜率最大的拐点作切线,得参数L 和T,则齐格勒-尼柯尔斯法参数设定如下: (a) 比例控制器: (b) 比例-积分控制器: , (c) 比例-积分-微分控制器: , 对于低增益时稳定而高增益时不稳定会产生振荡发散的系统,采用齐格勒-尼柯尔斯第二法(即连续振荡法)设定参数。开始只加比例校正,系统先以低增益值工作,然后慢慢增加增益,直到闭环系统输出等幅度振荡为止。这表明受控对象加该增益的比例控制已达稳定性极限,为临界稳定状态,此时测量并记录振荡周期Tu和比例增益值Ku。然后,齐格勒-尼柯尔斯法做参数设定如下: (a) 比例控制器:

人教版高中英语选修七Unit3Underthesea

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