2. Fill in the table.

Quantity	Names of Units	Symbol
Length		mm cm m km
Mass		mg gr kg
Volume		ml l cm3
Time		s min h

VIII. Listening

a. Listen to the song and fill in the missing words.

Now there's some matter here before me... What kind of matter could it be? I'll list some properties: • It's …... • It has its own …... • And it's ……. So what kind of matter could it be?

[Chorus] So when I wonder what can the matter be I'll make a list of its properties And when I'm finished then I can see If it's …… or it's …… or it's ……. They're all around us in every place They all have ……. and they take up …… But everyone is a special case It's a solid or a liquid or a gas. There's other matter here before me... What kind of matter could it be? I'll list some properties: • It can be ….... • It changes ……. • And it's …….. So what kind of matter could it be? [Chorus] There's still more matter here before me... What kind of matter could it be? I'll list some properties: • It's ……. the room. • It …… …….. . • And it's …….. . So what kind of matter could it be?

XI. Writing

Choose one topic and write a composition (80-100 words).

1. What distinguishes solids, liquids, and gases from each other?

2. What are ‘intermolecular forces’? How are these related to the three states of matter?

X. Grammar. Infinitive

a. Read and translate the following sentences.

1. To use the energy of a moving body was proposed in the early days of mechanics.

2. Recently they have done a lot of work to investigate the effect concerned.

3. D. I. Mendeleev was the first to arrange the elements according to their atomic masses.

4. The element 101 was the first to have been given the name of a Russian chemist.

5. It is too early to discuss the results.

6. He is unlikely to come tomorrow.

7. To know the quantity of energy present in a body is very important.

8. To obtain these results a lot of work had to be done.

9. To describe this phenomenon you must introduce new data.

10. He didn`t know where to find the necessary information.

b. Open the brackets using infinitive or gerund.

1. I enjoy (study) languages.

2. Mary stopped (go) to the English class.

3. Do you mind (wait) a few minutes in the hall?

4. Let me (give) you a few examples of what I mean.

5. They have finished (paint) the motor-car at last.

6. I was pleased (see) him.

7. I ought to (speak) to your mother first.

8. Peter was driving fast and could not avoid (hit) the other car.

9. You shouldn`t risk (drive) a car if you have a cold.

10. I dislike (ride) a bicycle.

11. I went to the shop (see) what I could buy.

12. It is a question of (find) the book.

13. She suggested one evening we should (drive) to the nearby village.

14. That book is worth (read), of course. But you can`t (read) it in the car.

15. He has had very little experience of (teach).

16. Peter and Mary are (think) of (move) to another town.

UNIT 8

Basic elements: Hydrogen and Oxygen I. Lead-in a. Fill in the gaps in the sentences with the following words and expressions: depend on, combine, characteristics, periodic table, reducing, odorless, oxidizing, differ in, vital.

Oxygen and hydrogen share some common ……….. . They are gaseous, ……….. and colorless elements. They ……. to form water, which is …….. for all living things. All living things …….. …. oxygen and hydrogen directly and indirectly. Although oxygen and hydrogen have similarities, they ……. from each other … certain respects. Oxygen belongs to the group 16 elements while hydrogen is the first element in the ……. ……. . Oxygen contains 8 electrons and 8 protons unlike hydrogen, which has one electron and one proton. Oxygen is accounted for nearly 21% of the earth’s atmosphere, but only a negligible amount of hydrogen is present in it. Oxygen is an …….. agent, but hydrogen is …….. agent.