Everyone wants to reduce pollution. But pollution problem is ________ (1) complicated as it is serious. It is complicated ________ (2) much pollution is caused by things that benefit people. For example, exhaust ________ (3) automobiles causes a large percentage of all air pollution. But automobiles provide transportation for millions of people. Factories discharge much of the material ________ (4) pollutes the air and water, but factories give employment to a large number ________ (5) people. Too much fertilizer or pesticide can ruin soil, but fertilizers and pesticide are important aids to the growing of crops. Thus, to end or reduce pollution immediately, people would have to stop using many things that benefit ________ (6). Most people do not want to do that, of course. But pollution can be gradually reduced in several ways.

Do factories discharge a lot of the material that pollutes the water?

Complete the second sentence so that it has the similar meaning to the first.

The author has written a special edition for children.

→ A special edition …………

We ________ (not meet) our classmates since we left school.

Complete the passage with the words in the box, then answer the questions bellow.

Everyone wants to reduce pollution. But pollution problem is ________ (1) complicated as it is serious. It is complicated ________ (2) much pollution is caused by things that benefit people. For example, exhaust ________ (3) automobiles causes a large percentage of all air pollution. But automobiles provide transportation for millions of people. Factories discharge much of the material ________ (4) pollutes the air and water, but factories give employment to a large number ________ (5) people. Too much fertilizer or pesticide can ruin soil, but fertilizers and pesticide are important aids to the growing of crops. Thus, to end or reduce pollution immediately, people would have to stop using many things that benefit ________ (6). Most people do not want to do that, of course. But pollution can be gradually reduced in several ways.

They were having dinner _________ I arrived.

She went to bed early because of her sickness.

→ Because she …………

Choose the underlined word or phrase (A, B, C or D) that needs correcting.

Would (A) people be able to (B) fly if they have (C) feathers instead of (D) hair?

Choose one word whose underlined part is pronounced differently from the others.