Concordancing in Japanese TEFL: Unlocking the power of data-driven learning

Gregory Hadley

hadley@nuis.ac.jp

 

 

As the TEFL community continues in its paradigm shift away from an emphasis upon fluency (Willis and Willis 1996), teachers world-wide over the past several years have become increasingly interested in concordancing as a tool for language learning.  Concordancing is a technique in which a large body of text (called a corpus) is analysed by a computer program to discover the regular patterns and lexical sets that are associated with a specific word or phrase. By studying this data, teachers and students can make certain generalisations as to how a certain lexical item is normally used. Figure One shows a small sample concordance for the word interesting, which was drawn from both spoken and written sources.

 

The data can be manipulated, depending upon the complexity of the program, to display the concordanced word (called the key word) in complete sentences, or to show frequently-occurring words (called collocations) that occur only on the left or the right of the key word. Concordancing is often used by teachers as a means to provide hard data to either back up or refute their subjective judgements on difficult questions of a grammatical nature. Students with access to concordancing data normally use it for error analysis or as an aid to improve their reading and writing skills.

 

Concordance of interesting (Source: text of 17 million words in the Nagaoka Kosen Corpus)

           

1          o the locations of their sources. It is interesting to speculate what the source

2          d produce a top quark. The rest, though interesting for a host of other projects         

3          silicates. Carbonates Are Key  The most interesting aspect of ALH84001 are the c

4          ty‑three days." JUMPING FISH‑‑"The most interesting examples of amphibious fishe

5          the mechanisms of its action will prove interesting to deduce. Some studies have  

6          cally, but it would still be undeniably interesting and valuable to know how a p          

7          ids.  NANCY COLLINS (on camera)  It`s interesting because there are so many

8            several of the bidders. They had some interesting reasons for why they were he   

9          s great crime prevention, and it's very interesting.  ROBERT KRULWICH (intervie

10        may be part of it. However, there is an interesting development in Hollywood, wh

11        on. "I've got it. You don't." With one interesting exception. If a guy is in a       

12        DONALDSON By the way, here’s something interesting -- James Patterson says

13        born again. So it was a really, really interesting thing. You know in the Pente           

14        OKS Well, I think that one of the other interesting objects in the sale that the 

 

Figure 1

 

Most of the foreign language learning which draws from corpora, often called Data-Driven Learning or DDL, seems to be intended for upper intermediate or advanced learners. This has been a major barrier to its use in Japan, where most learners rarely progress beyond the low intermediate level (Helgeson 1993, Richards 1993). This is not a problem specific only to Japan. Johns (1991a) remarked rather dryly that language teachers all over the world have made the same point:

 

Talking about the DDL approach with other language teachers I am sometimes reproached that while this way of language‑teaching by stimulating student questions and by doing linguistic research in the classroom on a cooperative basis may be very well for students as intelligent, sophisticated, and well‑motivated as ours at Birmingham University, it would not work with students as unintelligent, unsophisticated and poorly‑motivated as theirs (p.12).

 

Could corpora work with Japanese beginning or low intermediate learners of English?  When I ask my colleagues in Japan, I am often told that DDL is too hard for beginners, students will find it uninteresting, or that it is unlikely students will learn anything practical from such an approach. Finding an opportunity to see if these views are actually valid had been difficult - until recently.   

 

Teaching Environment

For the past year, I have been using a data-driven approach with beginning-level learners at the Nagaoka National College of Technology. This is a unique school where students complete a specialized high school education and two years of college study in engineering, applied science or industrial chemistry.  My classes consisted mostly of high school sophomores. The textbook was an English reader that was approved and “recommended” by the Ministry of Education (Keirinkan 1996). It is a rather grim little book consisting of short articles explaining mostly the cultural differences between Japanese and people from other countries. However, the language of the book is replete with artificial, contrived sentences aimed at teaching certain grammatical points. My position was not an enviable one: Teaching a form-based textbook to several classes of 40+ students, with only 50 minutes a week allotted for each class. However, the burden was somewhat lightened by the fact that all the classes were studying the text with a Japanese English teacher another day during the week. In these classes, they students used a Grammar-Translation method for studying the text. My approach was to respect the pedagogic decisions of my colleagues, and try to find a methodology which could in some manner complement what they were doing. Since data-driven learning is, at its core, a methodology which focuses on the form of the language, I felt that concordancing might be a helpful tool for my classes to better deal with the grammatical and lexical items in the textbook.

 

Process

Much of my methodology used for creating the classroom tasks came from Batstone’s (1995) concept of Manipulation-Regulation-Abdication. From this nexus, I started out by introducing the learners to a large amount of concordance material which has been selected in advance by the teacher. The learners are called on to identify any regularities in the data, and discuss it with the teacher or other students. They then attempt to manipulate the material in a number of simple writing tasks. Their progress was regulated by diagnostic tests throughout the units. Finally, control of the material was abdicated to the students, and they were allowed to apply it in open-ended writing tasks. The attempt is to move from a product approach to teaching towards a process approach, with data-driven learning as a pedagogic linking technique to bridge the gap.  Dudley-Evans (1997) recently stated that data-driven learning works best with teaching lexis and sentence-level writing skills, and this is what we focused on in the class, since other classes in the school deal with academic writing, conversation, listening and other skills.

 

A week before each class, I would go through the textbook unit to find any regularity in the short essays. When a certain lexical phrase or verb tense is used three or more times in a paragraph, it is a fairly good indication this is something the Ministry wanted students to learn. Using WordSmith Tools 2.0 (Scott 1997) and the 17 million word corpus compiled this year at the Nagaoka National College of Technology, I created concordances which attempted to demonstrate how the items in the textbook are used in authentic English Texts.

  

Before giving the students copies of the concordances, however, they began each unit with a needs test which helped them discover for themselves which grammatical items they may need to focus on during the course. Afterwards, they were given the concordance sheets, and a task which was a simplified version of those found in the COBUILD grammar workbooks (cf. Goodale 1995). During the process of writing down several authentic examples of the lexical or grammatical items which were the focus of study, it was hoped that the students would become aware of certain regularities in the text -  a cognitive process which is called consciousness-raising (Rutherford and Sharwood-Smith 1985). However, to make sure they are picking up these aspects of the language, a reference sheet which explicitly shows some of the major clusters around the lexical items was also given to the students. In the next class the students would be given another test to see if they had modified their language output as a result of the new data they had studied the week before. Later the learners were allowed generalize their knowledge by putting away their data sheets and writing their own sentences. Samples of all of this material can been seen in Appendix One.

 

Results

So far I have noticed a pleasant improvement in the writing skills and test scores of most of my learners. Those who studied and regularly attended classes are writing sentences and using the lexis from the text much more naturally than before. Of course there are other regular mistakes which crop up in the learners’ writing, but these are usually centered on things which were not covered in class. When these arise, I simply can go back and provide more data from the corpora to help them revise their work.  One added bonus has been that some learners, after being exposed to authentic data, have started to see why the language used in the school reader is sometimes stilted and unnatural.

 

I have found that the students are generally interested in corpora-based language learning, partly perhaps because as future scientists and engineers they tend to enjoy solving problems and researching data. However, because the students are high beginners, I must to limit the amount of data they receive so as not to overload them.  They also can become bored very quickly if I do not give them a variety of activities in class. For this reason, I will use the data in any number of activities, from as simple as crossword puzzles or bingo games where they must listen for certain items, to grammar-based activities which can be found in a number of teachers’ resource books (cf. Rinvolucri 1992). In some ways my classes have changed only in that the English being chosen and used has been taken from authentic material, not that which has been artificially manipulated in one way or another for the sake of the learner.

 

Problems with Data-Driven Learning

No method or technique is perfect, and a number of problems with using DDL with beginners surfaced during the course of the year. One which was mentioned earlier was the amount of data the learners could be exposed to. Some students would become quickly overwhelmed and demotivated if I provided them with too much data. Yet if not enough data was provided, how could I know they had received sufficient exposure to the grammatical or lexical items?  A more serious problem, however, was the difficulty of the concordance material. While the focus of the concordances was at the level of the students, the vocabulary and sentence structure which collocated with the key words was often way beyond their level of ability. I was locked in a quandary: simplify the concordance material and lessen its authenticity, or maintain the authenticity and risk demotivating some students because of the difficulty of the material. I opted to keep the material authentic, and some students did as a result begin to throw up their hands in despair near the end of the course. Others, however, rose to the challenge, and appeared to recognize the value of working with real English as opposed to “textbook” English. It was a difficult call for me, and I certainly would not criticize a teacher who chose to simplify the material according to the students’ level of proficiency. Another problem was the time it took for me to develop and copy materials for students. While it was worth the effort in my estimation, it would have nice if each student could access the corpus material  from the college’s computer network. This may become a possibility in the next couple of years, but abdicating control of the teaching material too soon might not be the best approach for younger students.        

 

Conclusion

While it admittedly takes a lot of time to develop the materials, I have found that a conscientious use of corpora overall has been a valuable teaching resource for my classes. The level of motivation of many of my students differed, but most seem to be interested in working with authentic data over the material presented in the textbook. Over time the discoveries students make from this form of study did seem to result in an improvement in their writing skills. Future corpora-based projects at this school includes the development of a lexically-based EAP course for the college level students as a means of preparing them for upper undergraduate and graduate studies. We will also be developing an advanced writing course for professors at the college, which will help them hone their skills for writing research papers.  We have only started to unlock the potential that DDL has for language learning in Japan. The next few years promise to be both exciting and challenging.

 

 

References

 

Batstone R. 1995. Grammar. Oxford: Oxford University Press.

 

Dudley-Evans T. 1997. Plenary Address on Recent Developments in ESP. Delivered at the Japan Conference of English for Specific Purposes, University of Aizu, Japan.

 

Goodale M. 199. Collins COBUILD Concordance Samplers 2: Phrasal Verbs. London:  HarperCollins Publishers.

 

Helgeson M. 1993. Dismatling a Wall of Silence: The ‘English Conversation’ Class’ in Wadden P.(Ed) A Handbook for Teaching English in Japanese Colleges and Universities pp.37-49. Oxford: Oxford University Press.

 

Johns T. 1991a. Should you be persuaded: Two examples of data‑driven learning in Johns, T. and King P.(Eds.) Classroom Concordancing pp. 1‑13. Birmingham: ELR.

 

Milestone 2 English Course. 1992. Tokyo: Keirinkan.

 

Richards J. 1993. Real-World Listening in the Japanese Classroom in Wadden P. (Ed) A Handbook for Teachng English in Japanese Colleges and Universities pp. 50-62. Oxford: Oxford University Press.

 

Rinvolucri M. 1992. Grammar Games. Cambridge: Cambridge University Press.

 

Rutherford W. and Sharwood-Smith M. 1985. Consciousness Raising and Universal Grammar. Applied Linguistics 6/3 pp.247-282.

 

Scott M. 1997. WordSmith Tools 2.0. Oxford: Oxford University Press.

 

Willis J. and Willis D. 1996. Challenge and Change in Language Teaching. Oxford: Heinemann.

 

 

Appendix

Reading Pretask

 

Instructions   With a group of three or four people, look at the words below.  These words will be in the story your are going to read.  What is the subject of the story?  Write the subject in the center of the mind map below:

 

 

 

The subject of the story you will read is _________________________________.  With the same group, write three questions that you want to ask about this subject.

 

 

1.

 

2.

 

3.

 

 

Now read the story.  Answer the questions.  Write new vocabulary in your "Putting it Together" worksheet.

 

 

Oval Callout: Use these maps to help you remember important words!

Putting it Together: Memory Maps

 

 

 

 

 

 

 

 

 

 

 


 

 


Checking the Dictionary

 

Use this worksheet to write the definitions or meanings of the vocabulary words in your native language.  Remember – sometimes a word in English can mean several words in your language.

 

Word in English

Word in your native language

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Words in Context

 

Instructions:  One word has been taken out of each group.  Put the words back in the correct groups

 

 

1 organelles would simply not contain the necessary ________ for metabolism and other life activities

2  rubber cements and are used for bonding flexible ________ such as paper, textiles, and leather.Med

3 and for locating deposits of natural construction ________ such as sand and gravel.  Victor C. Miller

4 g the colonial era to move minerals and other raw ________ to seaports for export.  Roads and railr

5 ssembly operations, and shortages of imported raw ________ and spare parts have forced factories to

6 Alluvial gold was the first of the important raw ________ that the states monopolized in order to

7 dge over the others by controlling sources of raw ________ overseas--in East and South Asia and in

8  terra-cotta, mud, beadwork, ivory, and other ________.  In southern and eastern Africa are found

9 duced chemical fertilizers, pesticides, and other ________ that greatly increase farm yields (altho

 

1 s the region's eastern border. The average annual ________ is 13 deg C (55 deg F), and the rainfa

2 olute zeroAbsolute zero is the lowest theoretical ________, representing the complete absence of

3 presenting the complete absence of heat.  At this ________ matter would possess zero ENTROPY

4 .Absolute zero is the lowest point of an absolute ________ scale.  Such a scale can be establishe

5 e of a trapped volume of gas as a function of its ________ in ordinary Celsius or Fahrenheit degr

6 isplay a linear relationship between pressure and ________ under conditions not far from ambient;

7 ressure becomes zero defines the absolute zero of ________.  The extrapolation is necessary becau

8 etermined is -273.15 deg C (-459.67 deg F).  This ________ is the zero point of the absolute Kelv

9 the zero point of the absolute Kelvin and Rankine ________ scales.  One Celsius degree and one

 

1 izontal-vertical position, Mondrian exerted great ________ both on architecture and on painting, fr

2 Beginning in the 19th century, mainly through the ________ of  KIERKEGAARD, religion was

3 cculturation  In anthropology, acculturation is the ________ of one society or ethnic group on anothe

4 s that occur in a nonindustrial society under the ________ of a complex Western society. An example

5 omplex Western society. An example of this is the ________ of American culture on the native tribes

6  many groups.  In the United States, the profound ________ of Viola Spolin, who created a systemati

7 During the 1950s the Actors Studio had a profound ________ on American theater, training for the st

8 (42 deg F).  The interior highlands are under the ________ of a continental climate and have severe

9 -the Sun, the Moon, and the stars--had a profound ________ on the activities of humans.  Thus, for

 

1 established the Carl Zeiss Foundation for scientific ________ and social improvement; in 1896 he

2 epartment's chief explosives advisor. In 1889 his ________ into the properties of GUNCOTTON led

3 ug to be tested and made available for continuing ________ into its uses against diseases such as ca

4  Reagan administration banned federal funding of ________ using fetal tissue obtained from induced

5 academic levels, to teach, publish, and engage in ________ unhindered by others.  Those protected

6 edom, in turn, have the responsibility to conduct ________ honestly, to report their findings accura

7 ic series Memoires, offered prizes for scientific ________, and supported several important scientif

8 795. It served as an active center for scientific ________ and debate until the 1830s. Today it cont

9 planned to have a single center for teaching and ________ that would bring together experts in al

 

1 ables the spectroscopist to readily determine the ________ of the absorbing material. The absorption

2 opy, and high-speed centrifugation to analyze the ________ of ion pumps. Radioactive tracers have b

3 red to sustain their own productivity.  Where the ________ of these systems is disturbed through hu

4 om covalently bonded to the carbonyl carbon.  The ________ of aldehydes is often written as RCHO.

5 A microphotograph reveals the ________ of Hydrodictyon, a species of algae. 

6 substance.  With the determination in 1988 of the ________ of the IgE receptors on mast cells, rese

7 uce L. La RoseBibliography:  Collet, Leon W., The ________ of the Alps (1974);  Engel, Claire E., T

8  and the threat of impending divine judgment. The ________ of the book falls into nine parts, each

9 the world depended on their sharing a common ________, the ________ of logic.  Thus what Russ

 

1 rganizations, both private and governmental.  The ________ tables, divided into several categories,

2 SSC.  First ground for the project was broken the ________ year, despite continuing political objec

3  in an annual report.  The statements include the ________:  The balance sheet compares the firms's a

4 onitrile to be a potential carcinogen, and in the ________ year the U.S.  government set standards

5 ut the production of art centers primarily on the ________ questions:  What is the role of genius,

6 he ancient civilizations of North Africa, see the ________ articles:  AFRICAN PREHISTORY;

7 ter elections in 1979, but lost the office in the ________ year's voting under a new constitution,

8 ping out of a bottle.  But clicks function as the ________ consonants do in the Roman alphabet:  p,

9 es for a modifier meaning "that" are shown in the ________ examples:  mtu yule ("that person"), wat

 

1   distortion, in which imaged lines bend ________ inward (pincushion effect) or outward (barr

2   Fluid injected into the cavity may be ________ a saline solution or hormones called PROSTA

3 ed of a speed in a given direction, any change in ________ speed or direction represents an accelerati

4 ssolved in water they are separated (dissociated) ________ partially or completely into charged partic

5 forces results in CAPILLARITY, in which a liquid ________ rises or falls in a fine tube.

6 in--have been replaced or modified by synthetics, ________ used alone or added to natural adhesives.

7 flexible, and more procedurally expeditious than ________ Congress or the courts could provide.

8 career is finally chosen. Adolescent girls who ________ marry early or make no career plans beyond

9 ater self-confidence than those whose parents are ________ overly permissive or authoritarian.

 

1 (1985 est.  pop., 500,566) is the major port and ________ center of northeastern Scotland.  Locat

2 ducers; mahogany, ebony, and okoume are the major ________ woods.  Ocean ________ fishing

3 hy and how Western influence would benefit Africa.  ________ interests were also important,

4  Later it functioned primarily as the center of ________ life in the city; markets were held her

5 cient and backward.  Coffee is the most important ________ crop.  (Image Bank)Coffee, Brazil's

6  Complete Airbrush Techniques for ________, Technical, and Industrial Applications

7 k, on the Lim Fjord.  It is an important port and ________ center.  The population is 113,650 (198

8 dy growth followed, and the city was a prosperous ________ center by the 17th century.  The

9 as the Egyptian Riviera.  The West Harbor is the ________ center and has numerous warehouses

 

 1 f a vapor.  Aerosols in which the particles are ________ the same size (monodisperse) are often prep

2  children, secondary schools were functioning in ________ all provincial towns, and the national univ

3 border points, and a network of airports connects ________ all of the provinces. Substantial natural-g

4 til the 19th century.  By the early 20th century ________ all of Africa had been subjected to Europea

5 has the highest fertility rates in the world, and ________ half its population are under 15 years of a

6 many of which are beyond its ability to control.  ________ three-fourths of all African nations are de

7  The descendants of the first group now inhabit ________ all of Africa south of an imaginary line ac

8 corn and wheat adaptable to subtropical regions.  ________ 50% of the world's wheat land was sown

9 atmosphere. Although the principal gases are ________ transparent to radiation, the tiny amounts

           

1 often using only a few micrograms because of the ________' scarcity and intense radioactivity. 

2 M--are included in the class.Although none of the ________ are found in nature in their pure metalli

3 al. Dreiser felt that the story contained all the ________ of American national life: "Politics, soc  

4 o describe the balanced reciprocal changes of the ________:  they perish into the things from which

5 Annunziata, Florence). In his later works the ________ of movement and vigorous action are incre

6 use of Christ's words of Institution, and of the ________ ordained by Him";  (4) "The Historic Epis

7 is a compound produced by removing water or the ________ of water from an acid or a base. Acid

8 ach interspersed with lines characteristic of the ________ present, a powerful new tool was given to

9 and they are also the means by which all of the ________ in the universe other than hydrogen have

 

These are the words to choose from:

elements  materials  nearly  temperature  either  influence  commercial  structure  following  commercial research

 

 

 

Understanding a Word

What does it mean to "understand a word"?  This is not an easy question to answer.  In this course, to understand vocabulary, we will look at things such as word families, clusters (chunks) and sentences.

 

Word Families

 

 

To "understand" a word, you need to know what "family" the word belongs to.  Below are the most common words that you will find somewhere near the word gasoline.

 


N

WORD

 

TOTAL

1

GASOLINE

 

562

2

THE

 

408

3

AND

 

288

4

ENGINE

 

84

5

ARE

 

78

6

ENGINES

 

77

7

FOR

 

76

8

FUEL

 

71

9

USED

 

56

10

OIL

 

53

11

THAT

 

49

12

WITH

 

48

13

PETROLEUM

 

44

14

COMBUSTION

 

40

15

DIESEL

 

38

16

MORE

 

37

17

OTHER

 

36

18

SUCH

 

35

19

AUTOMOBILES

 

35

20

WHICH

 

35

21

FROM

 

33

22

GAS

 

32

23

PRODUCTS

 

32

24

POWERED

 

32

25

OCTANE

 

29

26

AUTOMOBILE

 

29

27

USE

 

27

28

THAN

 

26

29

LEAD

 

25

30

INTERNAL

 

25

31

MOST

 

25

32

WERE

 

24

33

HIGH

 

23

34

KEROSENE

 

23

35

ALSO

 

22

36

INTO

 

22

37

AIR

 

22

38

POWER

 

21

39

WAS

 

21

40

MIXTURE

 

21

41

THEY

 

20

42

CAN

 

19

43

MANY

 

18

44

HAS

 

17

45

FIRST

 

17

46

UNITED

 

17

47

PRODUCTION

 

16

48

ENERGY

 

16

49

CARS

 

16

50

RUN

 

16

51

THIS

 

16

52

ELECTRIC

 

16

53

FUELS

 

15

54

STATES

 

14

55

MAKE

 

14

 


           

Reading Task

Read the article on gasoline.  Underline the words from this list that you find in the article. 

 

Word Clusters

Below are some of the common "chunks" that can be found with or near the word gasoline.

 

N

Cluster

Frequency

1

such as gasoline

13

2

the gasoline engine

13

3

a gasoline engine

10

4

of the gasoline

10

5

of gasoline and

9

6

high-octane gasoline

8

7

internal-combustion engine

8

 

 

 

 

Sentences

Here are some sentences that contain "chunks":

 

N         Concordance

1                    When such petroleum is heated, the lighter oils in it, such as gasoline and kerosine, are driven off, leaving the heavy, sticky asphalt.

2                    Crude oil is fed through a maze of pipes, towers, and vessels after which it appears in the form of usable products such as gasoline, jet fuel, and lubricating oil.

3                    Grease solvents derived from petroleum, such as gasoline and naphtha, were used. These are highly flammable, however. 

4                    Blazes in flammable liquids such as gasoline, oil, or grease are termed Class B.

5                    A carburetor is a device that vaporizes a liquid fuel such as gasoline and mixes it with air in the proper ratio for combustion in an INTERNAL-COMBUSTION ENGINE, such as the gasoline engine that powers most AUTOMOBILES.

6                    Automobile bodies and engines were made smaller and lighter to save gasoline. Researchers worked on alternatives to the gasoline engine and on fuel-efficient transportation.

7                    The development of the gasoline engine is generally attributed to Karl Benz and Gottlieb Daimler of Germany in about 1885.      

8                    Developments during the next 30 years included the gasoline-electric bus, which had a gasoline engine that drove a direct-current generator.

9                    The diesel engine was first developed by the German engineer Rudolf Diesel, who tried to improve on the efficiency of the steam engine and of the gasoline engine, which was invented shortly before (  Diesel, Rudolf).     

10                Finally, electricity and the gasoline engine made windmills obsolete.

11                In 1892 John Froelich, an Iowa blacksmith, built the first farm vehicle powered by a gasoline engine.

12                The internal-combustion engine, run by gasoline, became the chief power source for the farm.

13                Gasoline is burned in an internal-combustion engine to provide energy to power automobiles, airplanes, and other machinery. In some English-speaking countries, such as the United Kingdom, gasoline is referred to as petrol.

14                Gasoline to which TEL has been added is called ethyl gasoline. An internal-combustion engine runs best on a fuel that burns smoothly without exploding, or knocking.

15                Almost any liquid or gaseous fuel, however, can be used in an internal-combustion engine, including gasoline-alcohol mixtures called gasohol, alcohol, methane gas, and compressed coal gas.

16                For example, heavy fuel oil can be converted into high-octane gasoline by dividing, or "cracking, " the fuel oil's large, heavy molecules into small, light ones.

17                The reformate is used to make aviation fuel and to blend with straight-run gasoline to make high-octane gasoline.

18                The alkylate is then used to make high-octane gasoline.  The finished gasoline is made in a gasoline plant. The straight-run gasoline, cat-cracked gasoline, gasoline from thermal cracking and hydrocracking, reformate, butane, and alkylates. 

19                The single major cause of air pollution is the internal-combustion engine of automobiles. Gasoline is never completely burned in the engine of a car, just as coal is never completely burned in the furnace of a steel mill.          

20                A proper combination of these oxides gives their surface highly acidic properties that are useful in catalyzing the production of high-octane gasoline.  All of the gasoline used in the United States is processed by a catalytic reaction carried out over an alumina silicate called zeolite.

 

Gasoline

 

Gasoline, _______________ as petrol in England, is a petroleum HYDROCARBON fuel _______________ principally to power internal-combustion engines.  Composed primarily of the alkanes (see ALKANE) hexane, heptane, and octane, it is liquid at ordinary temperatures but evaporates easily in air to form a flammable mixture.

 

Production

Gasoline can be produced by distilling crude oil--that is, by maintaining the oil at high temperatures until the different oil components, or "fractions," reach boiling point and vaporize.  Simple distillation converts only _______________ 10% of a barrel of crude oil to gasoline.  The "cracking," or further breaking down, of heavy oil fractions under high temperatures and pressures produces _______________ 25%.  In catalytic cracking, a process that converts even higher percentages of oil into gasoline, the oil is fed in a stream of steam into a reaction vessel containing a catalyst.  In "reforming," the gasoline fraction is mixed with hydrogen over heat in the presence of a catalyst, causing a rearrangement of its molecular structure and creating a product that performs _______________ efficiently in internal combustion engines (see PETROLEUM).

 

Composition

Before they are ignited by a spark plug, the hydrocarbons in a gasoline blend _______________ ignite spontaneously under the high temperature and pressure conditions inside an engine cylinder. This preignition causes a characteristic engine knock.  The OCTANE NUMBER is a measure of the fuel's ability to resist preignition.  It is obtained by comparing the gasoline's antiknock performance with that of a mixture of octane and heptane:  a gasoline blend with an octane number of 90 equals in performance a mixture of 90% percent octane and 10% heptane. The octane number of a gasoline can be increased by the use of reforming techniques and by alkylation, where gasoline components are recombined to build a larger molecule with a high octane number.

The volatility of gasoline--its ability to vaporize easily--is an important characteristic, insuring trouble-free engine starting in cold weather.  In winter, therefore, volatility is raised and the flash point is lowered by adding extra butanes and pentanes.  To prevent "vapor lock" in warm weather, less volatile mixtures that will _______________ vaporize in the fuel lines are produced.

 

Additives

A number of additives are incorporated into commercial gasoline blends.  _______________ of _______________ inhibit oxidation and gum formation _______________ storage.  Dyes _______________ be added for identification purposes. Alcohol and surfactants are _______________ to reduce carburetor icing and corrosion.  Detergent additives remove from the engine and fuel injector _______________ of the deposits that are the products of gasoline combustion.

 

These are the words that you may use in the blanks above.  It is possible to use these words more than one time

 

not    more   about     may   some            used   these              during    known

 

 

 

Gasoline

 

Gasoline, known as petrol in England, is a petroleum HYDROCARBON fuel used principally to power internal-combustion engines.  Composed primarily of the alkanes (see ALKANE) hexane, heptane, and octane, it is liquid at ordinary temperatures but evaporates easily in air to form a flammable mixture.

 

Production

Gasoline can be produced by distilling crude oil--that is, by maintaining the oil at high temperatures until the different oil components, or "fractions," reach boiling point and vaporize.  Simple distillation converts only about 10% of a barrel of crude oil to gasoline.  The "cracking," or further breaking down, of heavy oil fractions under high temperatures and pressures produces about 25%.  In catalytic cracking, a process that converts even higher percentages of oil into gasoline, the oil is fed in a stream of steam into a reaction vessel containing a catalyst.  In "reforming," the gasoline fraction is mixed with hydrogen over heat in the presence of a catalyst, causing a rearrangement of its molecular structure and creating a product that performs more efficiently in internal combustion engines (see PETROLEUM).

 

Composition

Before they are ignited by a spark plug, the hydrocarbons in a gasoline blend may ignite spontaneously under the high temperature and pressure conditions inside an engine cylinder. This preignition causes a characteristic engine knock.  The OCTANE NUMBER is a measure of the fuel's ability to resist preignition.  It is obtained by comparing the gasoline's antiknock performance with that of a mixture of octane and heptane:  a gasoline blend with an octane number of 90 equals in performance a mixture of 90% percent octane and 10% heptane. The octane number of a gasoline can be increased by the use of reforming techniques and by alkylation, where gasoline components are recombined to build a larger molecule with a high octane number.

The volatility of gasoline--its ability to vaporize easily--is an important characteristic, insuring trouble-free engine starting in cold weather.  In winter, therefore, volatility is raised and the flash point is lowered by adding extra butanes and pentanes.  To prevent "vapor lock" in warm weather, less volatile mixtures that will not vaporize in the fuel lines are produced.

 

Additives

A number of additives are incorporated into commercial gasoline blends.  Some of these inhibit oxidation and gum formation during storage.  Dyes may be added for identification purposes. Alcohol and surfactants are used to reduce carburetor icing and corrosion.  Detergent additives remove from the engine and fuel injector some of the deposits that are the products of gasoline combustion.

 

 

 

Writing Task

With a partner, on a piece of notebook paper, write seven sentences using the word gasoline.  Be sure to use what you've learned from looking at the word family and clusters section.