English Ludmila Plamadeala
UNIT 10
ROCKS
1 What are fossils?
The study of geology can tell us a lot about early history and about the
creatures which once lived on earth. If a prehistoric animal died in an area
where the soil was moist and alkaline, it would possibly be preserved.
Over a period of millions of years, the soil would turn into stone and the
creature, or its bones, would be fossilised. Skeletons and shells of all sorts
of organisms, from elephants to snails, have been found as fossils.
Geologists can date them according to the layer and type of rock in which
they are found. Some types of rock, such as clay shale, are richer in fossils
than others.
fossils
2 How is coal formed?
Geologists are also interested in the mineral content of rocks. All rocks consist of one or more minerals many
of which are needed as raw materials for industry or have properties which make them valuable or useful. Gold,
for example, is valuable. Diamonds are both valuable and useful. Coal is also found in rocks, usually
underground, and it is vitally important as a fuel in modern life. Britain is rich in coal because it was covered in
dense forest more than 300 million years ago. Coal is formed from the remains of trees and other plants which
have gradually been compressed and hardened in the rock structure of the earth.
3 How are minerals extracted from rocks'.'
A number of different processes have been developed for extracting minerals from ore. Some, such as copper,
lead and iron, are extracted by heating the ore up, usually in a furnace, until the mineral melts and
separates from the rocks. This process is called smelting. Other minerals require different treatment.
Aluminium, for example, is usually extracted from its ore by electrolysis, a process which uses electricity to
break down a compound.
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WORDS
WORD STUDY
prehistoric (1): from times before history was first recorded. We know about prehistoric animals from fossils,
not from any written reports.
preserved (1): kept in good condition. The pyramids and some other ancient buildings have been well
preserved.
clay shale (1): a type of rock. Bricks and pots may be made of clay which is usually reddish-brown in colour.
mineral (2): a natural substance contained in rock or in the earth.
raw materials (2): the basic things needed in industry to produce finished goods.
remains (2): the things left over after a process has ended, e.g. the remains of a meal. This word is
always used in the plural.
ore (3): rock which contains metal.
furnace (3): a container in which metals and other substances can be heated to very high temperatures. A
furnace is used in the production of steel.
WORD BUILDING
1. Look at these pairs of words and complete the list
rich - enrich circle - . . .
able enable large - …
danger - endanger sure- …
close - enclose
2. Now look at this list and complete it
black - blacken thick- …
dark - darken short- …
hard - harden wide-…
long (length) - lengthen strong (strength)- …
light - . . . white- …
moist - . . . soft- …
sweet -. . . deep- …
Whether en is used at the beginning or at the end of a word, the meaning is the same. To enlarge means to
make larger; to lighten rneans to make lighter.
3. Now replace the words in italics in each sentence by a verb from one of the two lists above
a) Farmers have different ways of making the soil richer"•
b) Sugar can be used to make tea sweet.
c) The runways at London Airport had to be made longer to make the
big jets able to land.
d) The tiger has been put into danger by hunting.
e) A telescope makes us able to observe distant planets and stars.
f) Leather has to be made softer before it can be used for shoes.
g) Clouds usually make the sky dark before a storm.
h) After using an electrical instrument, you should always make sure that it is switched off.
QUESTIONS AND ANSWERS
1. Answer these questions
a) What sort of soil preserves well?
b) Which part of an animal is hardest and lasts longest?
c) How can geologists find out how old a fossil is?
d) Do all types of rock contain a lot of fossils?
e) Does acidic soil preserve well?
f) What is coal formed from?
g) What is a furnace for?
h) What is smelting?
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English Ludmila Plamadeala
2. Make questions for these answers, using the words in brackets
a) Clay shale does. (What sort of. . . ?)
b) Alkaline soil does. (What sort of. . . ?)
c) In the earth. (Where . . . ?)
d) Over 300 million years ago. (When . . . ?)
e) It is the rock which contains metal. (What. . . ?)
f) No, it isn't. It is usually found underground. (Is . . . ?)
g) No, they aren't. They are extracted by different processes. (Are. - - •
h) No, it isn't. It is extracted by electrolysis. (Is . . . ?)
SENTENCES AND PARAGRAPHS
CONNECTIVES
Look at this example
Q: In what circumstances would you ask a geologist for information ?
A: If I wanted to know something about rocks or minerals.
1. Now answer these questions in the same way, using If. . .
a) In what circumstances would you use a microscope?
b) In what circumstances would you look at a compass?
c) In what circumstances would you look at a thermometer?
d) In what circumstances would you use a computer?
e) In what circumstances would you look at the word list at the back of this book?
2. Here are some split sentences. Find the right ending for each one.
a) I would look at a barometer if I wanted to measure a line.
b) I would look at my watch if I wanted to know about his theory.
c) I would go to see a doctor if I wanted to know the time.
d) I would wear glasses if I wanted to weigh something.
e) I would read Darwin's book if I felt sick.
f) I would use a ruler if I wanted to multiply 3-749 by 43^.
g) I would use a calculator if I were short-sighted.
h) I would use a balance if I wanted to know the air pressure.
Look at these examples
Diamonds are valuable and useful, too.
Diamonds are both valuable and useful.
That text book is not interesting, and it isn't useful either.
That text book is neither interesting nor useful.
3. Now rewrite these sentences with both . . . and or neither . . . nor
a) Amphibians live on land and in water, too.
b) Oxygen is colourless and tasteless, too.
c) Some minute organisms are not plants and they are not animals,
either.
d) Gold is not mined in Britain and silver isn't, either.
e) Carbon atoms can form rings and chains, too.
f) Water is not an acid and it isn't an alkali, either.
g) There is no water on the moon, and no oxygen either,
h) Copper is a metal. Aluminium is a metal, too
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RELATIVES
Look at this example
Q: What does the age of a fossil depend on? (layer and type of rock/ found)
A: It depends on the layer and type of rock in which it is found.
4. Now answer these questions in the same way
a) What does the success of a farmer's crops depend on? (soil/grown)
b) What does the quality of a metal depend on? (ore/found)
c) What does the climate of an area depend on? (part of the world/ situated)
d) What does the taste of a type of tea depend on? (area/grown)
Look at these examples
All rocks consist of one or more minerals. Many of them are needed as raw materials.
A11 rocks consist of one or more minerals, many of which are needed as raw materials.
All his friends live in London. Most of them are doctors.
A11 his friends, most of whom are doctors, live in London.
5. Now make single sentences from these pairs of sentences in the same way
a) All tigers are in danger of dying out. Many of them live in India.
b) Hydrocarbons consist of carbon and hydrogen. Most of them can be produced from coal or oil.
c) Industrial geologists analyse rock samples. Many of them work for big oil companies.
d) Hovercraft are being used more and more. Some of them are jet propelled.
e) All Sweden's lakes are polluted. Many of them are very beautiful.
f) Metals are generally found in rocks. Most of them are solids
THE PASSIVE
Look at this picture
The two scientists are coming to the end of their day's work, but there are some things which have to be done
before they can go home.
Look at this example
The light is on. It has to be switched off.
6. What else has to be done ? These sentences will help you.
a) The apparatus is dirty.
b) The microscope is out on the table instead of in the cupboard.
c) The window is open.
d) The jars of chemicals are still open.
e) The bunsen burner is burning.
f) The battery is still connected up.
g) The text books are still open on the table,
h) The door of the laboratory is still open.
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English Ludmila Plamadeala
GUIDED WRITING
Look at these two graphs
The first one represents imports of aluminium and aluminium alloys* to Britain between 1938 and
1973. The second one represents exports of the same substances over the same period.
* mixtures of different metals.
Imports
(in thousand
of tonnes)
These graphs give information quickly and easily.
7. Why would it be difficult to show both imports and exports on the same graph?
Look at this example
In 1938, Britain imported 52,800 tonnes of aluminium and aluminium alloys, and exported 6,400 tonnes.
Imports exceeded exports by 46,400 tonnes.
8. Now write about each year in the same way.
Read this paragraph
Between 1938 and 1948, annual exports of aluminium and its alloys increased steadily from under 10,000
tonnes to about 65,000. Over the following ten years, there was a marked decrease to 37,000 tonnes, but by
1968 Britain was again exporting over 60,000 tonnes annually. For the next three years, the figures remained
fairly steady, showing a slight increase to 74,000 tonnes by 1971. A very sharp rise followed in 1972 when
121,000 tonnes were exported. Exports reached a new maximum in 1973, with a total of 139,000 tonnes.
6. Now write a similar paragraph about imports, based on the first graph.
ARITHMETIC
MENTAL ARITHMETIC
1. Work on these questions with a friend. Remember, mental arithmetic is done in the mind not on paper
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English Ludmila Plamadeala
a) Yesterday, a car travelled non-stop from Liverpool to London at a speed of 40 m.p.h. The distance is 200
miles. How long did the journey take?
b) Oil is pumped into a 2,000 gallon tank at a rate of 4 gallons per second. How long does it take to fill
the tank?
c) Willy's car does 35 miles per gallon of petrol. A gallon of petrol costs 80 pence. (lOOp = £1). How much
will it cost Willy to get from Liverpool to London and back?
d) Joe goes shopping with $6.50 in his pocket. He buys a pound of bananas for 70 cents, a loaf of bread
for 60 cents and four rump steaks for $2.90. How much money has he left when he gets back?
IDENTIFICATION AND CLASSIFICATION
Look at this example
Q: Which pairs belong together? diamonds, iron, copper, coal
A: Diamonds and coal belong together because they are both carbon
compounds. Iron and copper belong together because they are
both metals.
1. Now put these into pairs and give reasons
b) methane, carbon dioxide, argon, benzene.
d) 4,9, 11, 14.
f) sandstone, glass, clay shale, plastic.
g) an oil barrel, a football field, a page in this book, a turbine pipe.
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