4. recycle- won't produce

5. don't water- will die

6. is- won't go

7. will save- don't waste

8. will happen- keep

9. don't stop-will endanger

10. dump-won't be able

V. Write the first conditional sentences

1. If you work hard, you won't pass the exam

2. If Henry fails his examination, his parents will be sad

3. If Sue go out this weekend, she won't have time to study

4. If it snows tomorrow, I won't go skiing

5. If he leaves soon, he won't miss the bus

6. If you play with matches, you will hurt yourself

VI. Complete the sentences with your own words

1. we can save our planet

2. the environment will become less polluted

3. we don't deforest

4. we pollute the ocean

5. you can save a lot of water

VII. Underline the correct words

1. recycled

2. reusable

3. reduce

4. off

5. recycled

6. less

7. reuse

8. save

4. If everyone recycles paper, metal, and glass, we won't produce so much rubbish.

5. If you don't water plants, they will die.

6. If the weather is bad, we won't go to the park.

7. We will save thousands of trees if we don't waste so much paper.

8. What will happen if we keep polluting the environment.

9. If we don't stop cutting down so many trees, we will endanger our oxygen supply.

10. If people dump chemicals into rivers, they will not be able to swim in them in the future.

V.

1. You should work hard, or you won't pass the exam.

⇒ If you don't work hard, you won't pass the exam.

2. Henry fails his examination. His parents will be sad.

⇒ If Henry fails his examinnation, his parents will sad.

3. Sue shouldn't go out this weekend, or she won't have time to study.

⇒ If Sue go out this weekend,she won't have time to study.

4. I think it'll snow tomorrow, I will go kiing.

⇒ If the weather'll snow tomorrow, I will go skiing.

5. He should leave soon, or he'll miss the bus.

⇒ If he don't leave soon,he'll miss the bus.

6. Don't play with matches. You will hurt yourself. 

⇒ If you play the matches,you'll hurt your self.

VI.

1. If we all use reusable shopping bags, the world can become cleaner.

2. If more people cycle, the amount of smoke and dust will be reduced.

3. We will save a lot of trees if we can plant more trees.

4. A lot of fish will die if ocean polluted.

5. If you have a shower instead of a bath, we can save a lots water.

VII.

1. These materials are recycled / reduced into other packaging products.

2. These containers are refutable / reusable. You can use them again.

3. Try to reduce / reuse the amount of wastes you produce.

4. Please turn the television on / off before you go to bed.

5. Take these old newspapers to the recycling / recycled bin.

6. If more people cycle, there will be less / more air pollution.

7. Recycle / Reuse old clothing by donating it to a local charity.

8. We can waste / save a lot of trees if we recycle waste paper.