Part 1. Adaptation

Exercise 1. Read the following sentences and choose the right modal verb and the form of infinitive using the information from the table above:

Some modal verbs are used more than once:

can, could, has to, had to, must, mustn’t, shouldn’t, might

Each infinitive form is used only once:

be touched, fly, be, be provided, start, be eaten, look for, be living, eat, adapt, be caught, have been connected, survive … reproduce, have been digested

1. The example of evolutional adaptation can be provided by the giraffe.

2. When much of the grass in Africa dried giraffes … the leaves of the trees.

3. Some giraffes with the longest necks … and ….

4. The soil is very poor, so the Venus’s flytrap … another way of feeding.

5. A bug … near by Venus’s flytrap.

6. If a bug is unlucky enough it … by the plant.

7. The bristles of the plant are sensible so they … otherwise an insect … .

8. The bug which was caught yesterday … completely.

9. The leaf … again when the bug is completely digested.

10. Some living things … easily, while others cannot.

11. Some scientists believe that extinction of dinosaurs … with sudden changes in the climate of earth.

12. Humans … happy that with special equipment they … anywhere on earth.

Part 2. Mass Extinction

Exercise 2. Rewrite the following sentences in passive voice:

1. A hostile environment causes the mass extinction today. V1=cause(reg.)

2. The Europeans discovered North America in the late 1400s. V1= discover(reg.)

3. The earth will lose more than a quarter of total number of species. V1=lose(irreg.)

Exercise 3. Rewrite the following sentences in active voice:

1. The extinctions today are being caused by humans’ activities. V1=cause(reg.)

1. Extinctions today are measured in terms of a human lifetime. V1=measure(reg.)

2. More than 60 species of North American vertebrates have been annihilated by humans’ activities. V1=annihilate(reg.)

Unit 9. Habitat is Becoming Hostile

Part 1. Hostile Habitat Causes Extinctions

Exercise 1. Read the following sentences and fill in the gaps with the right forms of the infinitive given below:

Each infinitive form is used only once:

have been protecting, have given, be done, save, be thinking, have been lost

1. People don’t seem to be thinking about environmental problems today

2. Only some of them realize that something should … about this.

3. To help the environment now is to … it.

4. Mass Media might … us more information about ecological situation in the world.

5. Scientists are sure that the lack of information on this problem led to many species to … forever.

6. Most of them are happy to … the environment for many years.

mass media [mæs ’mi:diə] – средства массовой информации

Exercise 2. Read the following sentences and fill in the gaps with the right modal verbs given below:

Some modal verbs are used more than once:

should/ shouldn’t, can/ can’t, must/ mustn’t, have, may

1. Most of mammals can swim and climb the trees.

2. Most of the birds … fly but some of them … , for example, kiwi or ostrich.

3. Most of the fish and marine animals … spawn but they … feed their young with milk.

4. Most of species … to survive in the habitat which is becoming hostile for them.

5. It is a fact that all living species … be protected today.

6. People … do something to protect the endangered species today.

7. What … be done for it?

8. First of all people … continue polluting the environment.

9. If we don’t stop to pollute the environment the rate of extinctions … increase.

10. People … be careless about this problem.

11. The tragedy of habitat loss … ever happen.