8. You are asking Helen questions beginning Have you ever……? Write the questions.

1. (London?) – Have you ever been to London? - No, never.

2. (play/golf?) - ………………………………………..? – Yes, many times.

3. (Australia?) - …………………………………………? – No. Never.

4. (lose/your passport?)………………………………..? – Yes, once.

5. (fly/in a helicopter?)…………………………………? – No, never.

6. (eat/Chinese food?)………………………………….? – Yes, a few times.

7. (New York?)……………………………………………? – Yes, twice.

8. (drive/ a bus?)………………………………………….? – No,never.

9. (break/ your leg?)……………………………………..? – Yes, once.

Get talking

1. Work in pairs. Discuss "The problems involved in laying a building's foundations". Your talk should last a minute.

2. Imagine you are a future skilled engineer. Give a summary of the text "Foundation " in 150 words.

_{Lesson 20}

The gravitational force

_{Grammar; Past Perfect Tense}

1. Read the previous text again and complete the sentences, predicting average future loads from vehicles on the bridge:

12. It is that the load will be less than 0 tones.

13. That the load will be 0-3 tones.

14. It is that the load will exceed 2 tones.

15. The most frequent load on the bridge will probably be between and tones.

2. Read the statements and say whether they are true or false. Correct the. false statements;

• Most of the components failed at a load between 1 /₂ and

1 % tones.

16. No components failed below a load of 1 ¹/_л tones.

17. Nearly all the components failed above a load of 1 y, tones.

18. Very few components failed over a lewd of 2 y_z tones.

19. If these components are used in a bridge which is loaded to destruction, they will probably fail at a load between 2 and 2 y_& tones.

3. Look at these diagrams of joints and answer these questions:

• For each joint, say how the units are joined together.

• Explain how forces are transmitted through each joint.

• In which joints can packing be used?

• In which joints should the joint surfaces be machined flat?

4. Write down all the nouns from the text in plural.

5. Match nouns and adjectives:

20. force "live"

21. loads exact

22. loads gravitational

23. value applied

24. loads "dead"

25. toads probable

6. Make the following sentences negative and put into the interrogative form:

I

• The gravitational force on a structure can be divided into dead loads and live loads.

• Live loads are always variable and movable.

• This condition is too dangerous.

• Structures must also resist wind or earthquakes.

• It is impossible to predict accurately the magnitude of ail the forces that act on a structure during its life.

7. Read the sentences. In each case, tick (V) which happened first, a) or b).

Example

It was late when I got home because I had worked late at the office.

a) I got home b) I worked late at the office V

1. I had a quick meal and I switched on the TV for the late night movie, “Alien Killers”.

a) I had a meal b) I switched on the TV

2. I went to bed as soon as the film had finished.

a) I went to bed b) The film finished

3. I saw a bright light at my window after I had got into bed.

a) I saw a bright light b) I got into bed

4. I had closed the windows but there was a strong wind in my room.

a) I closed the windows b) There was a strong wind

5. When the wind had gone away, I heard a strange voice.

a) The wind went away b) I heard a strange voice

6. When the voice had spoken, the bright light disappeared.

a) The vice spoke b) The bright light disappeared.