G1. Change the sentences according to the model and translate them.

A

Model 1: If he comes, we’ll discuss it. If he came, we would discuss it. If he had come, we would have discussed it.

1. If you interfere in their affairs, they’ll get angry. 2. If I keep him waiting, I’ll apologize. 3. If you explain everything, he’ll forgive you. 4. If you arrange to meet on Sunday, I’ll come too.

Model 2: It’s too cold. We won’t go bathing. If it were not so cold, we would/could/might go bathing.

1. He is too shy. He won’t dare to ask the question. 2.It’s too wet. We can’t play tennis. 3. He is not punctual. He won’t come in time. 4. His behavior was very strange. So we got suspicious.

G2. Complete the sentences using the words in brackets:

A

1.If you(heat) water to 100° C it (boil). 2. When you (boil) water, it (turn) into steam. 3. Steam (turn) back into water if you (cool) it. 4. A piece of metal (expand) when you (heat) it. 5. A piece of metal (contract) if you (freeze) it. 6. If weather patterns (change), draughts and floods (be) more frequent. 7. If rain (fall) at the wrong time, farmers (be) unable to grow their crops. 8. If rainfall (increase) there (be) more soil erosion and desert (spread). 9. Sea level (rise) if polar ice (melt). 10. Northern Europe (become) colder if the Gulf Stream (grow) weak.

G3. Use the words to complete an if- sentence about solutions to environmental problems:

A

Model: everyone/recycle paper/companies/not cut down so many trees

If everyone recycles paper, companies won’t cut down so many trees (optimistic!)

If everyone recycled paper, companies wouldn’t cut down so many trees (pessimistic)

If everyone had recycled paper, companies wouldn’t have cut down so many trees (pessimistic)

a) everyone/recycle metal and glass/we not waste valuable resources;

b) everyone/recycle paper, metal and glass/we not produce so much rubbish;

c) everyone/turn off unwanted lights/save a lot of electricity;

d) everyone/walk or cycle/not waste so much oil and petrol

e) everyone/insulate their houses/not waste so much energy for heating

f) countries use more wind and water power, not depend so much on power stations

g) countries use power stations less, cause less air pollution

G4 Complete the questions and try to answer them:

A, B

1. What/ happen if you/ travel through the Earth to the other side?

2. What/ happen if the Earth suddenly stop/ going round?

3. What/ happen if we not/have a moon?

4. What/ happen if all the ice at the poles/melt?

5. What/ happen if there be/ no more electricity?

6. What/ happen if aliens receive/ messages from the Earth and decide/ to visit us?

G5. Supply the correct form of the verbs in brackets.

A, B

1. If I bought him a computer he (play) games all day long. What about his lessons then? 2. If Sue had phoned me that the children were coming on Friday I (decorate) a Christmas tree by their arrival. 3. It (be) nice if they had liked each other. But they didn’t. What a pity! 4. They (be) a nice couple if they get married. 5. I (buy) a Mercedes if I could afford it. 6.You would feel better if you (not smoke). 7. If I (have) my car serviced regularly, it wouldn’t have broken down.