Question

[ĐZ Hòa]

IX. Choose the word which best fits each gap.
Many human activities over the last 200 years have been responsible (1) ____ polluting the air and
damaging people’s health. Automobile engines and power plants burn combustible (2) ____ like
gasoline and coal and allow toxic gases and smoke to escape into the air. Some pollutants destroy the ozone
layer, which is the thin blanket of gases that
(3) ____ Earth from the Sun’s dangerous ultraviolet rays. Other pollutants contribute to (4) ____
warming by adding to the planet’s natural greenhouse effect. Still others create acid rain, a phenomenon
that has disastrous (5) ____ on lake and forest habitats. Air pollution is not limited to industrial areas.
Depending on the direction of the wind and its force, air pollutants may (6) ____ spread to other
countries very far from the source of the pollution.
Big cities like Los Angeles and Mexico City are*often covered by smog, a fog that occurs (7) ____ air
pollution. In 1952, the City of London, England, was enveloped by smog so thick that people on the streets
had to feel their way around by (8) ____ the walls of buildings!
1. A. for B. of C. to D. with
2. A. chemicals B. means C. fuels D. matters

3. A. covers B. protects C. stops D. damages
4. A. environmental B. thermal C. temperature D. global
5. A. affects B. causes C. sources D. effects
6. A. never B. even C. ever D. hardly
7. A. because of B. in spite of C. instead of D. due of
8. A. climbing B. walking C. touching D. putting up