搜档网
当前位置:搜档网 › A Practical Tool for Visualizing and Data Mining Medical Time Series Li Wei

A Practical Tool for Visualizing and Data Mining Medical Time Series Li Wei

A Practical Tool for Visualizing and Data Mining Medical Time Series Li Wei
A Practical Tool for Visualizing and Data Mining Medical Time Series Li Wei

A Practical Tool for Visualizing and Data Mining Medical Time Series

Li Wei Nitin Kumar Venkata Lolla

Eamonn Keogh Stefano Lonardi

Chotirat Ann Ratanamahatana

Helga Van Herle

University of California, Riverside Department of Computer Science & Engineering University of California, Los Angeles David Geffen School of Medicine

{wli, nkumar, vlolla, eamonn, stelo,

ratana}@https://www.sodocs.net/doc/2918470264.html,

hvanherle@https://www.sodocs.net/doc/2918470264.html,

Abstract

The increasing interest in time series data mining has had surprisingly little impact on real world medical applications. Practitioners who work with time series on a daily basis rarely take advantage of the wealth of tools that the data mining community has made available. In this work, we attempt to address this problem by introducing a parameter-light tool that allows users to efficiently navigate through large collections of time series. Our approach extracts features from a time series of arbitrary length and uses information about the relative frequency of these features to color a bitmap in a principled way. By visualizing the similarities and differences within a collection of bitmaps, a user can quickly discover clusters, anomalies, and other regularities within the data collection. We demonstrate the utility of our approach with a set of comprehensive experiments on real datasets from a variety of medical domains.

1. Introduction

The increasing interest in time series data mining has resulted the introduction of a variety of similarity measures/ representations/ definitions/ indexing techniques and algorithms (see, e.g., [1][2][5][8][9][10]). Surprisingly, the massive research effort has had little impact on real world applications. Medical practitioners who work with time series on a daily basis rarely take advantage of the wealth of tools that the data mining community has made available. Possible reasons for this discrepancy are the bewildering number of parameters, the specialized hardware and/or software, and the long time learning required by the time series data mining tools.

In this work, we attempt to address this problem by introducing a parameter-light tool that allows users to efficiently navigate through large collections of time series. Our approach extracts features from a time series of arbitrary length, and uses the relative frequency of these features to color a bitmap. By visualizing the similarities and differences among the bitmaps, a user can quickly discover clusters, anomalies, and other regularities within the data collection.

Our system can both be used as an

interactive tool and be embedded directly

into any standard operation system. We

employ the bitmap representation as the

icon for time series file. Simply by

glancing at the icons of time series files,

a user can quickly identify files that

require further investigation. Figure 1

illustrates a simple example for four EEG time series. Time series example_a.dat is from a normal trace, whereas the others contain Figure 1. Four time series bitmaps.

examples of spike-wave discharges. The difference between one dataset and all the rest is immediately apparent from a casual inspection of the bitmap representation.

2. Background and Related Work

In this section, we give brief reviews of chaos games and symbolic representations of time series, which together are at the heart of our visualization/data mining technique.

2.1 Chaos Game Representations

Our visualization technique is partly inspired by an algorithm to draw fractals called the Chaos game [1]. The method produces a representation of DNA sequences, in which both local and global patterns are displayed.

The basic idea is to map frequency counts of DNA substrings of length L

into a 2L by 2L matrix as shown in

Figure 2, then color-code the frequency counts. The CGR representation of a sequence allows the investigation of the patterns in sequences, making it

possible for human eyes to recognize hidden structures.

In Figure 3, we take the first 5,000 symbols of the mitochondrial DNA sequences of four species and use them to create file icons. Note that

Pan troglodytes

is the familiar Chimpanzee, and

Loxodonta africana and

Elephas maximus

are the African and Indian Elephants,

respectively. Even if we did not know these particular animals, we would have no problem recognizing that humans and chimpanzees have similar genomes, as do the African and Indian elephants.

The results in figure 3 encouraged us to

try a similar technique on time series data. Since CGR is only defined for discrete sequences and most time series are real valued, a discretization method is necessary to transform continuous time series data into discrete domain. For this purpose, we used the Symbolic Aggregate approXimation (SAX) [11], as reviewed below.

2.2 Symbolic Time Series Representations

While there are at least 200 techniques in the literature for converting real valued time series into discrete symbols [3], the SAX technique of Lin et. al. [11] is unique and ideally suited for data mining. SAX is the only symbolic representation that allows the lower bounding of the distances in the original space. If a representation is tightly lower bounding the original data, it must be representing it with great fidelity.

Figure 2. The quad-tree representation of a sequence over the alphabet {A,C,G,T} at different levels of resolution.

Figure 3. The bitmap representation of the gene sequences of four animals.

CC CT TC TT

TC CA CG TA TG AC AT GC GT

AA AG GA GG

C T

A G

CCC CCT CTC

CCA CCG CTA CAC CAT

CAA

The SAX representation is created by

taking a real valued signal and dividing it into equal sized sections. By

substituting each section with its mean, a reduced dimensionality piecewise constant approximation is obtained. This representation is then discretized to

produce a word with approximately

equi-probable symbols. The whole

conversion process is shown in Figure 4. Users need to choose the length of the local sliding window N , and the number n of equal sized

sections in which to divide N . A good choice for N should reflect the natural scale at which the events occur in the time series. A good value for n depends on the complexity of the signal.

3. Time Series Bitmaps

At this point, we could combine the idea of Chaos game [1] and the SAX representation to get the bitmap representation for time series. We use SAX on alphabet size four because the Chaos game bitmaps are defined on sequence with alphabet size of four. We use simple alphabetical ordering as shown in Figure 5 as an initial ordering for the four SAX symbols a , b , c , and d .

After converting the original raw time series into the SAX representation, we count the frequencies of SAX “subwords” of length L , where L is the desired level of recursion. Level 1 frequencies are simply the raw counts of the four symbols. For level 2, we count pairs of subwords of size 2 (aa , ab , ac , etc.). Note that we only count subwords taken from individual SAX words. For example, in the SAX representation in Figure 5 middle right , the last symbol of the first line is a , and the first symbol of the second word is b . However, we do not count this as an occurrence of ab .

Once the raw counts of all subwords of the desired length have been obtained and recorded in

the corresponding pixel of the grid, we normalize

the frequencies by dividing them by the largest value. The pixel values P thus range from 0 to 1. The final step is to map these values to colors. In the example above, we mapped to grayscale, with 0 = white and 1 = black . However, it is generally recognized that grayscale is not perceptually

uniform [13]. A color space is said to be perceptually uniform if small changes to a pixel are approximately equally perceptible across the range of that value. For all images in this paper, we encode the pixels values to be [P , 1-P , 0] in the RGB color space.

It is important to note that we do not suggest any utility in viewing a single time series bitmap. The utility of the bitmaps comes from the ability to efficiently compare and contrast them.

4. Time Series Thumbnails

Figure 4. A real valued time series can be converted to the SAX word baabccbc.

Figure 5. The generation of time

series bitmaps.

abcdba aa ab ba bb ac ad bc bd ca cb da db cc

cd

dc dd

a b c d aaa aab aba aac aad abc aca acb acc

0230012111030

1

573

3

bdbadb cbabca

Level 1

Level 2

Level 3

020406080100120

-1.5

-1

-0.5

00.5

11.5

A unique advantage of the time series bitmap representation is that we can transparently integrate it into most standard operating systems. For time series files, we generate the bitmap representations and use them as the file icons. Simply by glancing the icons of time series files, a user may spot files that require further investigation or note natural clusters in the data.

Normally, file icons are arranged by one of a handful of common criteria, such as name , date , size, etc. To augment the utility of the time series bitmaps, we have created a simple modification of the standard Microsoft Windows (98 or later) file browser by introducing the concept of Cluster View . If Cluster View is chosen by the user, the time series thumbnails arrange themselves by similarity. This is achieved by performing Multi-Dimensional Scaling (MDS) of the bitmaps, and projecting them into a 2 dimensional space. Figure 6 displays an example of Cluster View in Microsoft Windows XP Operating System obtained for five MIT-BIH Arrhythmia Database

files. It is evident that eeg1.dat , eeg2.dat,

and eeg3.dat belong to one cluster

whereas eeg6.dat and eeg7.dat belong to another. In this case, the grouping correctly reflects the fact that latter two files come from a different patient to first three.

For bitmaps with same size, we define the distance between them as the summation of the square of the distance between each pair of pixels. More formally, for two n × n bitmaps BA and BB , the distance between them is defined as ∑∑==?=n

i n

j ij ij BB BA BB BA dist 112)(),(.

5. Experimental Evaluation

In this section, we will show some experiments that objectively measure the utility of our approach on classification, clustering, and anomaly detection. Since the quality of illustrations here suffers from monochromic printing and small-scale reproduction, we urge the interested reader to consult [6] for large-scale color reproductions and additional details.

5.1 Classification

For classification, we considered an ECG classification problem. Our ECG dataset is a four-class problem derived from BIDMC Congestive Heart Failure Database of four patients. Each instance consists of 3,200 contiguous data points (about 20 heartbeats) randomly extracted from a long (several hours) ECG signal. Twenty instances are extracted from each class (patient). We compared to the ubiquitous Euclidean distance [8][9][10] and DTW [6][12].

For both datasets, we use the one-nearest-neighbor with leaving-one-out evaluation method. The results are summarized in Table 1.

Figure 6. A snapshot of a folder arranged

by “Cluster” option.

Table 1: Classification error rates.

Euclidean DTW Bitmaps

ECG 42.25 % 16.25 % 7.50 %

We also considered a Normal vs Arrhythmia problem that appeared in [4]. Using Markov models, the authors reported an error rate of 2%. With our technique, under virtually any parameter settings, we achieve 0% error. We can achieve perfect classification using one nearest neighbor as above, or we can use MDS to project the data into 2- dimensional space and achieve perfect classification using a simple linear classifier, a decision tree or SVD. Figure 7 shows the data projected into 2D space, and the linear classifier learned (the gray line).

5.2 Clustering

We considered a four-class ECG clustering problem, where each class corresponds to a different patient. Figure 8 shows the clustering obtained with level 3 bitmaps, using parameters N = 150, n = 5. The results are correct, in that each time series from a given patient is assigned to its own sub-tree. For this problem, we found that we could vary the N and n parameters by a factor of 4 (N > n ) and still obtain the correct clustering.

Figure 7. Classification by projection.

Figure 8. Clustering results.

1

23451113121415691078161817192012732

2

4

56

7910

1112131415

16

17

19

21

2225

2628

2934

39454954

5.3 Anomaly detection

The time series bitmap distance measure allows the creation of a simple anomaly detection algorithm. We create two concatenated windows and slide them together across the sequence. At each time instance, time series bitmaps are built for the two windows and the distance between them is reported as an anomaly score.

Figure 9 illustrates the idea on some annotated ECG data. The top part is a subsection of an ECG dataset. A cardiologist annotated a premature ventricular contraction at approximately the 1.4 mark. The score in the middle shows a strong peak for the duration of the anomalous heartbeat. The bottom shows that the bitmaps before and after the peak are very different. Our approach easily detects the single anomaly shown, and the rest of the annotated anomalies in this dataset (not shown).

We have built an online version of

this tool [6], which the readers may investigate with their own datasets (or several built-in examples).

Reproducible Results Statement: In the interests of competitive scientific inquiry, all datasets used in this work are available at the following URL [6]. This research was partly funded by the National Science Foundation under grant IIS-0237918.

References

[1] Barnsley, M.F., & Rising, H. (1993). Fractals Everywhere , second edition, Academic Press.

[2] Berndt, D., & Clifford, J. (1994). Using dynamic time warping to find patterns in time series , AAAI Workshop on

Knowledge Discovery in Databases, pp. 229-248.

[3] Daw, C. S., Finney, C. E. A. & Tracy, E. R. (2001). Symbolic Analysis of Experimental Data. Review of

Scientific Instruments. (2002-07-22).

[4] Ge, X., & Smyth, P. (2000). Deformable Markov model templates for time-series pattern matching . In proceedings

of the sixth ACM SIGKDD, pp. 81-90.

[5] Jeffrey, H.J. (1992). Chaos Game Visualization of Sequences . Comput. & Graphics 16, pp. 25-33. [6] Keogh, E. https://www.sodocs.net/doc/2918470264.html,/~wli/CBMS05/

[7] Keogh, E. (2002). Exact indexing of dynamic time warping . In Proceedings of the twenty-eighth International

Conference on Very Large Data Bases, pp. 406-417.

[8] Keogh, E., Chakrabarti, K., Pazzani, M., & Mehrotra (2001). Locally adaptive dimensionality reduction for

indexing large time series databases . In Proceedings of ACM SIGMOD Conference on Management of Data.

[9] Keogh, E. & Kasetty, S. (2002). On the Need for Time Series Data Mining Benchmarks: A Survey and Empirical

Demonstration . In the 8th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining. [10] Korn, F., Jagadish, H., & Faloutsos, C. (1997). Efficiently supporting ad hoc queries in large datasets of time

sequences . In Proceedings of SIGMOD, pp. 289-300.

[11] Lin, J., Keogh, E., Lonardi, S. & Chiu, B. (2003) A Symbolic Representation of Time Series, with Implications for

Streaming Algorithms. In proceedings of the 8th ACM SIGMOD Workshop on Research Issues in Data Mining and Knowledge Discovery.

[12] Ratanamahatana, C.A., & Keogh, E. (2004). Everything you know about Dynamic Time Warping is Wrong . 3rd

Workshop on Mining Temporal and Sequential Data, in conjunction with the 10th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining.

[13] Wyszecki, G. (1982). Color science: Concepts and methods, quantitative data and formulae , 2nd edition. New

York, Wiley, 1982.

Figure 9. Time series anomaly detector.

英语作文关于共享单车的篇精编

(一) 假定你是红星中学初三学生李华。你的美国朋友Jim在给你的邮件中提到他对中国新近出现的一种共享单车“mobike”很感兴趣,并请你做个简要介绍。请你给Jim回信,内容包括: 1. 这种单车的使用方法(如:APP查看车辆、扫码开锁等); 2. 这种单车的优势; 3. 你对这种单车的看法。 注意:1. 词数不少于80; 2. 开头和结尾已给出,不计入总词数。 提示词:智能手机smartphone, 二维码the QR code 参考范文 Dear Jim, I’m writing to tell you more about the new form of sharing bike mobike mentioned in your latest letter. It’s very convenient to use if you have a smartphone. What you do is find a nearest mobikethrough the APP, scan the QR code on the bike, and enjoy your trip. Compared to other forms of sharing bike, the greatest advantage of mobike is that you can easily find one and never worry about where to park it. It is becoming a new trend as a means of transportation, which relieves the traffic pressure and does good to the environment as well. Hope to ride a mobike with you in China. Yours, Li Hua (二) 最近很多大城市都投放了共享单车(shared bikes),比如摩拜单车(Mobike)、Ofo共享单车等。由于它们方便停放,骑车也能起到锻炼身体的作用,作为代步工具很受大家欢迎。但是,各地也出现了很多毁车现象,比如刮掉车上的二维码(QR code)、上私锁等。 你对这种现象怎么看?你对共享单车公司有什么建议吗?写一篇符合逻辑的英语短文,80词左右。 参考词汇:bike-sharing companies 共享单车公司,Mobike 和Ofo 是两家共享单车公司,convenience 方便,register登记 参考范文 The shared bikes like Mobike and Ofo bring great convenience to people. You needn’t lock them by simply using your smart phone. They can take you where the subway and bus don’t go. And they can be left anywhere in public for the next user. However, bad things happen. Some people damage the QR code on the bike, or use their own lock, which causes trouble to other users. In my opinion, it’s difficult to turn these people’s ideas in a short time. Therefore, bike-sharing companies like Mobike and Ofo need to do something. For example, those who damage the bike should pay for their actions. Also, because people use their real name toregister as a user, it’s a good way to connect to one’s personal credit. In the end, what I want to say is to take good care of public services. (三) 共享单车(bicycle sharing)已成为时下最热的话题之一,请你就这一话题写一篇短文。内容须包括三方面:1. 共享单车蓬勃发展,成为社会热潮;2. 共享单车带来便利,但也存在问题;3. 我对解决问题的建议。 参考范文 Bicycle Sharing With the development of technology, bicycle sharing comes into people's lives. It becomes more and more popular and much news reported it. At the same time, we should see that there are some problems caused by bicycle sharing. On one side, bicycle sharing makes it very convenient of people traveling. You can find a bicycle anywhere at any time when you want to go out for a cycling, and the price of one trip is very low. It can save time for people. On the other side, its management is not perfect. Even kids can open the lock and ride the bicycle, there is no doubt that such behavior is very dangerous.

介绍北京的英语作文(2)

介绍北京的英语作文(2) AsBeijinghasbeenconfirmedhomecityofOlympics2008,the spiritofgreenOlympics,scientificOlympicsandhumanizedOlymp icwillsurelybringmoreandmorechangestoBeijing,promotethed evelopmentofsportsandOlympicsinChinaaswellasintheworld,a ndstrengthenthefriendlycommunicationsbetweenChineseandf oreignpeople. 篇六:Beijing BeijingisthecapitalofPeoplesRepublicofChinaandthenation scentreforpolitics,economyandculture.Itenjoysalongandrichhis tory.Therearenumerousheritagesitesandwonderfulexamplesof ancientarchitecture,suchastheworld-famousGreatWall,theTem pleofHeavenandtheForbiddenCity. Besidessightseeingplaces,therearemanydeliciousfoodsuch asPekingducksandBeijingsnacks.Beijingisreallyagoodplacetotr avel. 篇七:Beijing AsthecaptainofChina,Beijinghasbeenthemostpopularcityofchina。SomoreandmorepeoplewanttovisitBeijing.

七年级上册英语课堂练习册参考答案与提示(人教版)

人教版七年级英语上册《课堂练习册》参考答案与提示 Starter Units l - 3 【基础达标】 Ⅰ. 略Ⅱ. 1.BBC 2.CD 3.kg 4.NBA 5.UFO 6. CCTV 7. UN 8. PRC 8. DIY 10. DJ Ⅲ. l.you 2. English 3. Spell 4. color 5. yellow Ⅳ. 1.B 2.A 3.A 4.C 5.C 6.C 7.B 8.A 9. C 10. B 【综合运用】 Ⅰ.1. Good evening. 2. What color is the cup? 3. What's this in English? 4. Spell it, please. 5. How are you? 6. Hello ! Ⅱ. l.C 2.A 3.B 4.C 5.C 6.B 7.B 8.A 9. C 10. B Ⅲ. 1. Peter. 2. Anne. 3. She is fine. 4. He is fine. Ⅳ. l.am 2.is 3.Are 4,is 5.is 6.your 7. My 8. Its Ⅴ. l. It's an apple. 2. I'm fine, thanks. 3. P - E- N. 4.It's a map. 5.It's white. Ⅵ. ( A)l. Hello, David ! 2. How are you? 3. what's that in English? 4. What color is it? 5, Spell it, please. ( B)6. Are you Bob? 7. Are you Alice? 8. Nice to meet you, too ! 9. Can you spell "jacket", please? 10. Is this your jacket? Unit 1 My name’s Gina. 【基础达标】 Ⅰ. l. Her 2. Hell0 3. meet 4. your 5. His Ⅱ. L.I’m 2.what's 3.she's 4.my name's 5.it's Ⅲ. l.B 2.A 3.C 4.C 5.B 6.D 7.A 8.D 9. B 10. D Ⅳ. 1.F 2.A 3,C 4.B 5.D 6.E Ⅴ. 略 【综合运用】

汽车利弊英语作文4篇

[标签:标题] 篇一:关于汽车的英语作文 好的 Nowadays, with the rapid improvement of people’s living standards, cars have become an indispensable part of people's lives,so that more and more people have a car of their own, especially in cities. It brings some benefits for us but also causes many problems at the same time. For one thing,there’s no doubt that cars provide much convenience for people to go where they want to quickly and easily. Especially on weekday,driving a car can save a lot of time for us to go to work.When some places are too far away from our home, driving our own car is also convenient, we can go wherever we want. However,for another, too many cars will lead to the pressure of public transport, a series of problems will appear.First of all,it will bring about more air pollution,a large amount of polluted air given off by cars do great harm to our health.What’s more, as the existing roads are not so wide for the increasing number of cars,undoubtedly,traffic jams will become more and more serious. Last but not least, cars also place burden on the public facilities in providing more parking lots. As far as I am concerned,everything has its advantages and disadvantages. It’s high time that effective action must be token to limit the ever growing number of cars, the government should take measures to control the air pollution from the cars. Some roads should be widened and more new roads should be constructed. Only in this way,will people benefit from the popularity of cars. 坏的 Nowadays, with the rapid improvement of people's living standards, cars have become an indispensable part of people's lives,so that more and more people have a car of their own, especially in cities.It brings some benefit for us but also causes many problems at the same time. For one thing,it's no doubt that that cars provide much convenience for people to go where they want to quickly and easily. Especially on weekday,driving a car can save a lot of time for us to go to work.When some places are too far away from our home, driving our own car is also convenient, we can go wherever we want. However,for another, too many cars will lead to the pressure of public transport, a series of problems will appear.First of all,it will bring about more air pollution,a large amount of polluted air given off by cars do great harm to our health .What's more, as the existing roads are not so wide for the increasing number of cars,undoubtedly,traffic jams will become more and more serious. Last but not least, cars also place burden on the public facilities in providing more parking lots. As far as I am concerned,everything has its advantages and disadvantages. It's high time that effective action must be token to limit the ever growing number of cars, the government should take measures to control the air pollution from the cars. Some roads should be widened and more new roads should be constructed. Only in this way,will people benefit from the popularity of cars. 篇二:雅思作文高分范文:私家车的利与弊 智课网IELTS备考资料 雅思作文高分范文:私家车的利与弊

人教版七年级上册英语课文

七年级上册 第一单元 A2d Good afternoon! My name is Linda. Are you Helen Yes, I am. Nice to meet you , Linda. Nice too meet you , too. What’ her name She is Jane。 Is he Jack No, he isn’t .His name’s Mike. B2b name is Jenny Green. My phone number is 281-9176. My friend is Gina Smith. Her phone number is 232-4672. ’m Dale Miller and my friend is Eric Brown. His telephone number is 357-5689. My telephone number is 358-6344. name is Mary Brown. My friend is in China. Her name is Zhang Mingming. My phone number is 257-8900 and her number is 929-3155. 第二单元 A2d Sally: Good morning, Jane Jane: Good morning, Sally. Sally: Oh, Jane, this is my sister Kate .Kate, this is my friend Jane. Kate: Nice to meet you, Jane.

A和An的用法

A和An的意思其实是一样的,都表示一个或单数的意思。当修饰的名字开头是元音(特别注意:是发音是元音而不是字母是元音字母啊)时,用an,例如an interesting book,而a则用于辅音开头的单词,例如a happy ending 名词的第一个发音为元音音标时,用an eg: an eye, an ear 名词的第一个发音为辅音音标时,用a eg: a hand 英语字母u前面的不定冠词a,an 的确定让学生头痛,怎么掌握呢?很简单,U 发字母表音的单词前是a,不发字母表音的单词前是an: a university 一所大学 a useful book 一本有用的书 an umbrella 一把雨伞 an underground train 一部地铁列车 冠词一般位于所限定的名词前,用来署名名词所指的人或事物。冠词有不定冠词和定冠词两种。不定冠词有两个形式,即a和an。a用在以辅音音素开头的词前,如a book; an用在以元音音素开头的字母前,如an apple. a或an与可数名词单数连用,泛指某类人或某物中的一个。the既可以用在可数名词前,也可以用在不可数名词前,表示某个或某些特定的人或事物,也可以指上文提到过的人或事物。 the/an/a用法及区别: 冠词在英文中属于虚词,在句子里主要是对名词起限定作用。这类词的数量很小,但是其活动性却很大,很大。在英文中,a / an并不等于one 。 例:He only has one dictionary.他只有一本词典。(正确) He only has a dictionary.他只有一本词典。(错误) One minute is enough for me to do it . 我做这件事一分钟足够了。(正确) A minute is enough for me to do it . 我做这件事一分钟足够了(错误) 1)不定冠词在句子中最大的语法功能是:用在可数名词的单数形式前表示泛指--表明一类人或事物区别于它类。 例:I am a Chinese. 我是(一个)中国人。 This is a book. 这是(一本)书。 2)为了读音的方便,在以元音音素开头的可数 名词的单数名词前用an而不用a。当我们使用an时,条件有三:①这个名词的读音必须是以元音音素开头--即它的音标的第一个音素是元音,而不是说它是以元音字母开头。②它必须是个可数名词。③它还必须是个单数名词。我们常常见到这类用法: a university 一所大学an hour 一个小时 an orange 一只桔子an engineer 一位工程师 an ordinary man一个普通人 an honest person一位诚实的人

介绍北京的英语作文1篇 .doc

介绍北京的英语作文1篇 篇一MyFamily Ilovemyfamily,becauseIhaveahappyfamily. MyfatherisanEnglishteacher.HisnameisJacky.Heisthirty-eight.Helikesplay ingbasketball.What’smymotherjop?Issheateacher?Yes,you’reright!Mymotherisverykindandnice,sheisthirty-seven.Mymotherisalways laboriouswork.Ilovemyparents! OnStaurdayandSunday,Ioftengotothelibraryandplaythepiano,Myfathergot oplaybasketball.Sometimes,wewatchTVandlistentomusicathome. Ilovemyfamily.BecauseI’mveryhappytolivewithmyparentstogether! 篇二MyFamily MyFamily Everyonehasafamily.Weliveinitandfeelverywarm.Therearethreepersonsin myfamily,mymother,fatherandI.Welivetogetherveryhappilyandtherearema nyinterestingstoriesaboutmyfamily. Myfatherisahard-workingman.Heworksasadoctor.Healwaystrieshisbesttoh elpevery,patientandmakepatientscomfortable.Butsonetimesheworkssohard thathecan”trememberthedate.

(2017)七年级上册英语课堂

(2017)七年级上册英语课堂 作业本答案 Uint 1一、A) 1.What’s 2. card 3. last 4. seven/six 5. phoneB) 1-5 ACBCCC) 1. her 2. answer 3. first 4. your 5. I 6. eight 7. to meet8. is 9. Tony 10. its二、1-5 BCCCC 6-10ACACC 11-15CCACB三、1. telephone number 2. last/family name 3. in English 4. three; two5. an ; His四、1. How are 2. I am 3. it is 4. What is family/last 5. What color五、DACBE六、1-5 ABBAC 6-10AABAA七、A. 1. girl 2. 8932561 3. black 4. red 5. AmyB. 1. Linda 2. Cruisfe 3. 12 4. four 5. 473-2106八、 My name is Alice Smith. Alice is my first name. Smith is my family name. I am 13 yearsold. And I like red . I think it’s nice. My telephone number is 3258673.Unit 2一、A) 1.English 2.bag/backpack https://www.sodocs.net/doc/2918470264.html,puter 4. watch 5. Thank 6. sharpener 7. eraser 8. lost 二、B) 1.your 2.me 3.Her 4. that 5.keys 6. hisC) 1.Is 2.are 3.spell 4.is 5. isn’t 6. call二、1-5CBBBC 6-10CABAC 11-15 CACAC三、1.baseball; isn’t 2. not his 3. How ;spell 4. Is ;an 5. Excuse me 四、1. Is that 2. is not 3. What’s this 4. it’s not 5. call; at五、DACEB六、1-5ACCBC 6-10 DBCAD七、CACDA八、 Lost FoundA set of keys A backpack. Some booksMy name is Joae. And a pencilcase are in it.Please call 83602388 Call Mr. Green at 46300029Unit 3一、A) 1.sister 2. grandmother 3. photo/picture 4. cousin 5. uncle 6. parentsB) 1.my 2. those 3. friends 4. Her 5. grandparents 6. this 7. His 8. pictures

汽车的重要性《英语作文》

汽车的重要性《英语作文》 The automobile has become one of the most important means/ways of transportation in the world since it was invented. The automobile has completely changed the lifestyles of almost all the people in the world. In the past, animals like horses and camels were used for traveling and transporting goods. Automobiles are more comfortable and faster. Automobiles have also made it possible for us to transport large quantities of goods and people at the same time. Besides, the invention of the automobile has provided jobs for millions of people all over the world. 翻译: 汽车已经成为世界上最重要的交通工具之一,因为它是发明的。汽车已经完全改变了世界上几乎所有的人的生活方式。 在过去,像马和骆驼的动物被用来运送货物。汽车更舒适,更快速。汽车也使我们能够在同一时间运送大量货物和人。 此外,汽车的发明为全世界上百万的人提供了工作。

我想去北京英语作文

三一文库(https://www.sodocs.net/doc/2918470264.html,) 〔我想去北京英语作文〕 我想去北京的英语作文如何写?那么,下面是小编给大家整理收集的我想去北京英语作文,供大家阅读参考。 我想去北京英语作文1 I’d like to go to a beautiful place. I think it would be Beijing. Beijing is not only our capital city, but also a famous city with long history and wonderful culture. Beijing is also China’s political and cultural center. There’re many old places of great interest, such as the Great Wall, the Summer Palace, the Forbidden City, the Temple of Heaven, and Tiananmen Square. Once you see Tiananmen Square, you will think of Beijing. It has been the symbol of Beijing since 1949. 我想去北京英语作文2 I went to Beijing more than eight times. Beijing is the capital of China. It’s a big city. I am very familiar with Beijing. It takes an hour and forty minutes from Nantong to Beijing by plane. There are many tall buildings in Beijing. It’s a modern city. My family visited the Great Wall, the Summer

七年级上册英语课堂练习册参考答案与提示(人教版)

七年级上册英语课堂练习册参考答案与提示(人教版) 篇一:人教版七年级英语上册课本课堂接练习题及 2013年人教版七年级英语上册课堂配套练习系列——课堂接力 第starter单元人教版七年级英语上册Starter Unit 1-3课堂接力 文具大全p3 Look at(看) my pencil box(铅笔盒).It’s blue.It’s my pencil box. What’s in it? Look! This is a pen.It’s red. This is a pencil. It’s orange. And this is an eraser(橡皮). It’s white. My pencil box is big and nice(好看的). I like it. 根据短文内容回答问题: 1.What?s this?______________________ xK b1.C om 2.What color is the eraser?________________________- 3.What?s in the pencil box?__________________________ (文具大全参考答案:1.It?s a pencil box.2. It?s white.3.A pen,a pencil and an eraser. ) 完形填空p5 Hello,I Dale.Look at(看)this picture(画), please. in the picture? A map, a bed(床quilt, a jacket, a TV are in it. are the quilt and the jacket ? The quilt nice. It isn’t . It is white. jacket isn’t green. is brown.

汽车英文演讲稿

汽车英文演讲稿 篇一:汽车英语演讲稿 Good morning everyone ,today, the topic of my lecture(演讲) is “Do you love automobiles('tmbilz)”. before I start my speech ,I want to ask a question,did there anybody present had seen the movie”the Fast and the Furious['fjrs]”.There are many cars of different styles in the movie,for example ,when you see the movie,you can find roadsters(跑车) just like Porsche(保时捷) GT3,sports utility (通用的)vehicles (车)SUV such as Volkswagen ['f:lks,va:gn]Touareg ['twɑ:reɡ](大众途锐),even armored cars ,all of them are so powerful and beautiful. When I was a child,I dreamed I can have a car like FORD GT 40,this racing bike(跑车) is amazing and fantastic,but as time goes on ,my hobby is changing,now my favorite car is Jeep Rubicon,this is a car I really want ,it’s dynamic performance(性能) and off-road (越野) performance is top-ranking(一流的) ,which other ordinary SUV is unable to compare; the shape and color of this car is magnificent (华丽的) [mg'nfs()nt],and it’s gear-shift system(齿轮转

小学一年级介绍北京的英语作文

小学一年级介绍北京的英语作文 Beijing is an ancient city with a long history. Back in 3000 years ago in Zhou dynasty, Beijing, which was called Ji at the moment, had been named capital of Yan. Thereafter, Liao, Jin, Yuan, Ming and Qing dynasty all made Beijing their capital. Therefore, Beijing was famous for "Capital of a thousand years". The long history leaves Beijing precious cultural treasure. Winding for several kilometers in Beijing area, the Great Wall is the only man-made structure that could been seen in the space. The Summer Palace is a classic composition of ancient royal gardens, and the Forbidden City is the largest royal palaces in the world. Tiantan is where the emperor used to fete their ancestors, and also the soul of Chinese ancient constructions. The four sites above has been confirmed world cultural heritage by UNESCO. However, the best representatives for Beijing are the vanishing Hutongs and square courtyards. Through hundreds of years, they have become symbol of Beijing's life. Tian'anmen square being still brilliant today with cloverleaf junctions and skyscrapers everywhere, the old-timey scene and modern culture are combined to present a brand new visage of Beijing. As Beijing has been confirmed home city of Olympics 2008, the spirit of "green Olympics, scientific Olympics and humanized Olympic" will surely bring more and more changes to Beijing, promote the development of sports and Olympics in China as well as in the world, and strengthen the friendly communications between Chinese and foreign people. 北京是一个有着悠久历史的古城。 早在 3000 年前的周朝,北京,这叫霁,被命 名为首都燕。此后,辽、金、元、明、清都是北京首都。因此,北京著名的一千年 的“资本”。 悠久的历史使北京宝贵的文化瑰宝。绕组在北京地区几公里,长城是唯一的 人造结构,可以在空间。 颐和园是古代皇家园林的经典组合,和故宫是世界上最大 的皇家宫殿。 天坛是皇帝用来祭祀他们的祖先的地方,也是中国古代建筑的灵魂。 上面的四个网站已经确认被联合国教科文组织世界文化遗产。然而,北京最好的 代表是消失的胡同和广场庭院。数百年来,他们已经成为北京的生活的象征。天 安门广场到处都在今天依然灿烂的蝶式路口和摩天大楼的,古色古香的场景和现 代文化相结合,提出一个全新的北京的面貌。 随着北京 2008 年奥运会已被证实的家乡,精神的“绿色奥运、科技奥
1/5

七年级上册英语教学工作总结

2017-2018七年级上英语教学工作总结 要搞好七年级英语教学,取得良好的教学效果,必须认真研究七年级英语的各单元内容,并加以有机综合,形成适应自身教学的有效方法,下面把本学期的教学工作总结如下: 一、业务学习 坚持每周的业务学习,紧紧围绕学习新课程,构建新课程,尝试新教法的目标,不断更新教学观念。注重把学习新课程标准与构建新理念有机的结合起来。并将理论联系到实际教学工作中,更新观念,丰富知识,提高能力。另外,自觉学习教师职业道德规范和教师十不准等,严格按照教师职业道德规范和教师十不准要求自己。认真完成学校布置的各项任务。 二、教学方面 教学工作是学校各项工作的中心,一学期来,在坚持抓好新课程理念学习和应用的同时,我积极探索教育教学规律,充分运用学校现有的教育教学资源,大胆改革课堂教学,加大新型教学方法使用力度,取得了明显效果,具体表现在: 1、备课深入细致。平时认真研究教材,多方参阅各种资料,力求深入理解教材,准确把握难重点。在制定教学目的时,非常注意学生的实际情况。 2、注重课堂教学效果。针对七年级学生特点,坚持学生为主体,教师为主导、教学为主线,注重讲练结合。在教学中注意抓住重点, 突破难点。注意和学生一起探索各种题型,我发现学生都有探求未知的特点,只要勾起他们的求知欲与兴趣,学习劲头就上来了,如每节课后如有时间,我都出几题有新意,又不难的相关题型,与学生一起研究。 3、要进行一定数量的练习,相当数量的练习是必要的,练习时要有目的,抓基础与重难点,渗透数学思维,在练习时注重学生英语思维的形成与锻炼,有了一定的思维能力与打好基础,可以做到用一把钥匙开多道门。 4、注重学生兴趣的培养,多给学生讨论的机会与时间,有序组织学生进行组内合作讨论,通过讨论练习加深学生对于课堂内容的印象,让对教学内容不太熟练的学生可以在比较熟练的学生带领下,模仿练习对话,她自己的成就感也会比较强一些,有助于学生的积极性。 5、考前复习中要认真研究与整理出考试要考的知识点,重难点,要重点复习的题目类型,难度,深度。这样复习时才有的放矢,复习中什么要多抓多练,什么可暂时忽略,这一点很重要,会直接影响复习效果与成绩。另外还要抓好后进生工作,后进生会影响全班成绩与平均分,所以要花力气使大部分有希望的后进生跟得上。例如在课堂上,多到他们身边站一站,多问一句:会不会,懂不懂,课后,对他们的不足及时帮助,使他们感受到老师的关心,从而能够主动学习。

a和an的用法

a用在以辅音字母开头,或以读做辅音的元音字母开头的单词前面: a man一个男人 a university一所大学 a hat一顶帽子 a European一个欧洲人 a one-way street一条单行马路 an用在以元音字母(a,e,i,o,u)开头,或以不发音的h字母开头的单词前面:an apple一个苹果 an island一个岛 an uncle一位大叔 an onion一个洋葱 an egg一个鸡蛋 an hour一小时 an还用在发音以元音开头的单个字母前面: an L-plate一块“实习驾驶”车牌 an MP一个国会议员 an SOS一个呼救信号 an…x?一个x字母、X形的东西或未知数 a/an没有性的变化: a man一个男人 a woman一个女人 an actor一个男演员 an actress一个女演员

a table一张桌子 a/an不用在以下几种情况下: A 复数名词之前: a/an没有复数形式,所以a dog的复数是dogs,an egg的复数是eggs。 B 不可数名词之前(参见第13节): C 三餐名称之前,但这些名称前加形容词时除外: We have breakfast at eight. 我们8点钟吃早饭。 He gave us a good breakfast. 他请我们吃了一顿丰盛的早餐。 为了庆祝某事或特意为某人而举行的宴会之前要用冠词: I was invited to dinner(at their house, in the ordinary way). 他们邀请我吃饭(在他们家吃便饭)。 但是说: I was invited to a dinner given to welcome the new ambassador. 我被邀请参加欢迎新任大使的宴会。 A a/an和one(形容词) 1 计算时间、测量距离或重量等时,a/an或one可以用于单数的前面:£l=a/one pound一英镑 £ 1,000,000= a/one million pounds 100万英镑 (参见第三十六章。) 但是,请注意: The rent is £ 100 a week. 房租为每星期100英镑。

相关主题