Focus on Words

extraordinary floods, especially in India, Bangladesh, China and the United States.
There are two major causes of floods in these countries: great rivers (for example, the
Mississippi and the Ganges), and sea-storms whose tidal waves wash sea water all over
the coast.
<strong>Focus</strong> on Grammar
Articles
1. Insert articles where necessary
1. Population means ... number of ... people living in ... particular area.
2. ... population of ... world does not stay ... same.
3. At ... moment it is growing at ... increasing rate.
4. In ... fact, ... scientists believe that ... world population will increase until 2020, and
then stop growing.
5. However, .. things are not .. same in ... all parts of ... world.
6. At ... present in many Western industrial countries ... population is falling.
7. This happens because ... families are small, and ... health conditions are good.
8. In ... developing countries, on ... other hand, ... population is rising sharply.
9. In ... Ghana, for ... example, most families have several children.
10. They earn ... money and look after their parents in old age.
It or There?
2. Fill in it or there in each space.
Tropical forests grow near the Equator where ... is warm and wet. ... are only two
seasons, rainy and dry. ... is normally 20-25 O C in a tropical forest and ... is only a drop
of about 5 O C in the colder months. ... is a lot of rain. ... is poor soil , and ...is difficult
for plants on the forest floor to develop as tall trees (25-30 metres) block the light. ...
are many plants, birds animals and insects.
In temperate forests, ... are four seasons with a cold winter. ... is impossible for the
trees to grow all the year round in a temperate forest, and ... is a growing season of
only 140-200 days. As ... is cooler and drier here, trees are smaller, ... is more light in
these forests, and ... is common to find many animals and birds. Again, ... is a range of
forest types depending on the annual rainfall.
MIXED TENSES
3. Choose the right option.
Man (1) ... to make his life easier for many centuries. In doing so, he (2) ...
machines and instruments. They (3) ... and polluting the world we live in.
In this world around us there are two things that do not belong to any country: air
and ocean water. People (4) ... about the air and the water used by everyone. One of the
most important pollution problems (5) ... in the oceans. Many ships sail in the ocean
water – fishing ships, some ships carrying people, some transporting oil. If a ship (6) ...
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