2_kurs_4_semestr

EXERCISES

1. Claire has got a cold. She has gone to the doctor‟s. Look at the prompts and say what the doctor advises her (not) to do.

2. Look at the prompts given. In pair, ask and answer questions, as in the example.

SA: Why did he go to the supermarket yesterday?

SB: Because he had to do some shopping.

1.he / go to the supermarket / do some shopping

2.she / go to the post office / post some letters

3.they / call the babysitter / attend a meeting

4.he / call a taxi / go to the airport

5.she / buy a dictionary / translate a novel

6.they / go to a restaurant / entertain some clients

3. Fill in the gaps with don‟t/doesn‟t have to, didn‟t have to or won‟t have to.

1.Tomorrow is Saturday, so I …won’t have to…go to school.

2.I‘ve already finished my project, so I …do it in the holidays.

3.We bought a takeaway pizza last night, so we …cook dinner.

4.Tom and Mary have got a washing-machine, so they …go to the laundrette.

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5.Steve passed his driving test, so he …take it again.

6.Sally is very rich, so she …work.

7.They bought tickets in advance, so they …wait in the queue.

8.Jane‘s mother wakes her up, so she …use an alarm clock.

9.I have already read the book, so I …read it again.

10.Sam never makes a mess, so he … tidy his room very often.

4. Fill in the gaps with mustn‟t or needn‟t/don‟t have to.

1.A: You …mustn‘t…do that again! It was very naughty!

B:I‘m sorry.

2.A: Shall I put some petrol in the car?

B:No, you …. I did it this morning.

3.A: You …be late tonight.

B:I won‘t. I‘ll be home early.

4.A: Shall I give you a lift?

B:No, you …. I‘ll go by taxi.

5.A: You …forget to pay the bills today.

B:I‘ve already done it.

6.A: You …lose the money I gave you.

B:I‘ll put it in a safe place.

7.A: You …buy a gift for Daisy‘s birthday.

B:Alright. I‘ll just send a card.

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UNIT 11

Electric Circuit

Read the text and express its main idea.

The electric circuit is the subject to be dealt with in the present article. But what does that above term really

mean? We know the circuit to be a complete path which carries the current from the source of supply to the load and then carriers it again from the load back to the source.

The purpose of the electrical source is to produce the necessary electromotive force required for the flow of current through the circuit.

The path along which the electrons travel must be complete otherwise no electric power can be supplied from the source to the load. Thus we close the circuit when we switch on our electric lamp.

If the circuit is broken or, as we generally say ―opened‘ anywhere, the current is known to stop everywhere. Hence, we break the circuit when we switch off our electrical devices. Generally speaking, the current may pass through solid conductors, liquids, gases, vacuum, or any combination of these. It may flow in turn over transmission lines from the power-stations through transformers, cables and switches, through lamps, heaters, motors and so on.

There are various kinds of electric circuits such as: open circuits, closed circuits, series circuits, parallel circuits and short circuits.

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To understand the difference between the following circuit connections is not difficult at all. When electrical devices are connected so that the current flows from one device to another, they are said to be connected in series. Under such conditions the current flow is the same in all parts of the circuit, as there is only a single path along which it may flow. The electrical bell circuit is considered to be a typical example of a series circuit. The parallel circuit provided two or more paths for the passage of current. The circuit is divided in such a way that part of the current flows through one path, and part through another. The lamps in your room and your houses are generally connected in parallel.

Now we shall turn our attention to the short circuit sometimes called

―the short‖. The short circuit is produced when the current is allowed to return to the source of supply without control and without doing the work that we want it to do. The short circuit often results from cable fault or wire fault. Under certain conditions, the short may cause fire because the current flows where it was not supposed to flow. If the current flow is too great a fuse is to be used as a safety device to stop the current flow.

The fuse must be placed in every circuit where there is a danger of overloading the line. Then all the current to be sent will pass through the fuse.

When a short circuit or an overload causes more current to flow than the carrying capacity of the wire, the wire becomes hot and sets fire to the insulation. If the flow of current is greater than the carrying capacity of the fuse, the fuse melts and opens the circuit.

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Answer the following questions:

1)What is the electric circuit?

2)What is the purpose of the electrical source?

3)What happens if the circuit is broken?

4)What may the current pass through?

5)What are the kinds of electric circuits?

6)What does it mean to be connected by series?

7)What is a typical example of a series circuit?

8)When is the short circuit produced?

9)May the short cause a fire? If yes, why?

10)What is to be used to stop the current flow?

Draw an electrical schematic diagram of a circuit where a battery provides electrical energy to a light bulb.

What would have to happen in this circuit for it to become shorted? In other words, determine how to make a short circuit using the components shown here:

In real life, of course, short circuits are usually things to be avoided. Discuss why short circuits are generally undesirable, and what role wire insulation plays in preventing them.

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GRAMMAR

Should / Ought to

 We use should/ought to to give advice.

e.g. Young children should/ought to go to bed early.

should not/shouldn’t

You spend so much money on clothes ought not to/oughtn’t to

Ствердження/заперечення

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EXERCISES

1. Joan doesn‟t always do the right thing. What does her mother advise her to do? Use the prompts to make sentences, as in the example.

e.g. You should do your homework.

1)She doesn‘t do her homework.

2)She talks all the time.

3)She never washes the dishes.

4)She doesn‘t tidy her room.

5)She eats lots of chocolate.

6)She argues with her sisters.

7)She doesn‘t put her clothes away.

8)She never takes the dog for a walk.

2. Complete the sentences. Use should + one of these verbs:

1.When you play tennis, you …should watch…the ball.

2.You look tired. You …to bed.

3.You …your teeth after every meal.

4.The city museum is very interesting. You …it.

5.When you are driving, you …a seat-belt.

6.It‘s a good book. You …it.

3. a) Write sentences with I think…should…Choose from:

have a holiday go to university sell it go home now go to the doctor

1.It‘s late. …I think we should go home now…

2.Your car is very old. I think you …

3.They need a change. I …

4.He doesn‘t look well. …

5.She‘s very intelligent. …

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b) Write sentences with I don’t think…should…Choose from:

stay there go to work today get married phone them now

6.It‘s very late. …I don’t think you should phone them now…

7.They‘re too young. I don‘t think …

8.That hotel is too expensive for us. I …

9.You‘re not very well. …

4. Translate into English.

1.Тобі слід прочитати цю статтю.

2.Вам не треба було разказувати їй всю правду.

3.Нам треба було зробити все заздалегідь.

4.Ти б провідав свого хворого товариша.

5.Тобі не треба було йти туди без батьків.

6.Твоїй подрузі слід бути уважнішою на уроках.

7.Тобі слід було не брати кота додому.

8.Вам треба було підготуватись до екзамену краще.

9.Я чув, що ти ходив на нову виставу у нашому театрі. Мені треба її подивитися?

10.Йому слід бути обережнішим.

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