Different meanings of should and would різні значення дієслів should I would 


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Different meanings of should and would різні значення дієслів should I would



SHOULD

1) допоміжне дієслово від shall для утворення 1 особи однини і множини Future-in-the-Past при узгодженні часів. e.g. They insisted that we should stay to have dinner with them. Вони наполягали, щоб ми залишилися пообідати з ними.

2) модальне дієслово, яке виражає пораду, пропозицію. Має значення "слід", "треба", "необхідно". e.g. Do you think I should apply for this job? Ти гадаєш мені слід звернутися по цю роботу?

3) бере участь в утворенні Subjunctive Mood e.g. The party was great last night. I think that you should have come. Вечірка була гарною минулого вечора. Гадаю, тобі слід було б прийти.

Note: 1. Should використовується після:

1) дієслів: suggest, propose, recommend, insist, demand, require та інших

e.g. She demanded that he should apologize to her. Вона вимагала, щоб він вибачився перед нею.

2) прикметників: important, strange, funny, natural, essential, odd, typical, interesting та інших.

e.g. It is strange that he should be late. He's usually on time. Це дивно, що він може спізнитися.

Він звичайно приходить вчасно.

2. Should використовується тоді, коли той, хто говорить, очікує, що щось напевно трапиться: e.g. He should get the job. He has got the necessary qualifications. Він напевно одержить цю роботу. Він має необхідну кваліфікацію.

WOULD

1) допоміжне дієслово для утворення 2-ої та 3-ої особи однини і множини Future-in-the-Past при узгодженні чaciв:e.g. Ann promised that she wouldn't be late. Ганна обіцяла, що вона не буде запізнюватися.

2) для вираження дії, що часто повторювалася у минулому e.g. Being students we would have dinner in this canteen. За часів студенства ми, бувало, обідали у цій їдальні.

3) при утворенні Subjunctive Mood:

e.g. I wish the rain would stop. Я б хотів, щоб дощ перестав іти.

Note: Would використовується, коли мається на увазі не реальна, а уявна ситуація, e.g. If I had known the number, I would have phoned you. Якщо б я знав номер, то зателефонував би вам.

Exercises:

I. Define meanings of should and would in the following sentences:

1. It is important that the temperature in the boiler should remain constant.

2. We wish you would explain us this grammar rule once more.

3. The lecturer said that the students would be sent to the plants to get practical skills.

4. They tried, but the engine wouldn't work.

5. This instrument should be treated properly.

6. One should be careful working with poisonous substances.

7. You should return the book to the library soon as possible.

8. If he could come he would take part in the discussion.

9. He said he would work at this plant.

10.You should be careful working with sharp tools.

11.I wish you should be more attentive.

12.It would be better if you dot up earlier.

ІI. Use should or would in the following sentences:

1. I think the results of the experiments (should / would) be positive.

2. If I was offered the job I (should / would) take it.

3. It (should / would) be noted that space flight involves many different problems.

4. It is very important that physicists (should / would) solve the problem of control of dangerous radiations.

5. If it were possible to live on the Moon, people (should / would) be able to jump about six times as high as they could on the Earth.

6. We asked the teacher if he (should / would) help us with the translation of the article.

7. (should / would) like to carry on my research work in the field of artificial refrigeration.

8. We were told that we (should / would) make experiments under the directions of a skilled instructor.

9. What (should / would) you do if you lost your passport in a foreign country?

 

10. The demand is that all measurements (should / would) be made very accurately.

11. We used to live next to a railway line. Every time a train went past, the whole house (should / would) shake.

12. If you used this method the results (should/would) be correct

Read and translate the text:

TEXT A. CONDENSERS.

Both evaporators and condensers are heat transfer surfaces.

Heat from the hot refrigerant vapor passes through the walls of the condenser to the condensing medium. As the result of losing heat to the condensing medium, the refrigerant vapor is first cooled to saturation and then condensed into the liquid state.

Although brine or direct expansion refrigerants are sometimes used as condensing mediums in low temperature applications, in the great majority of cases the condensing medium employed is either air or water, or a combination of both.

Condensers are of three general types: (1) air-cooled, (2) water-cooled, and (3) evaporative. Air-cooled condensers employ air as the condensing medium, whereas water-cooled condensers utilize water to condense the refrigerant. In both the air-cooled and water-cooled condensers, the heat given off by the condensing refrigerant increases the temperature of the air or water used as the condensing medium.

Evaporative condensers employ both air and water. Although there is some increase in the temperature of the air passing through the condenser, the cooling of the refrigerant in the condenser results initially from the evaporation of the water from the surface of the condenser.

The function of the air is to increase the rate of evaporation by carrying away the water vapor which results from the evaporating process.

Answer the questions:

1. What is a condenser?

2. How many types of condensers are there in use?

3. What fluids are used as condensing mediums in different types of condensers?

4. What are the functions of the condensing mediums?

TEXT B. EVAPORATORS

Any heat transfer surface in which a refrigerant is vaporized for the purpose of removing heat from the refrigerated space is called an evaporator. Because of the many different require­ments of the various applications, evaporators are manufactured in a wide variety of types, shapes, sizes, and designs, and they may be classified in a number of different ways, such as type of construction, operating condition, method of air (or liquid) circulation, type of refrigerant control, and application.

Evaporators fall into two general categories, flooded and dry expansion, according to their operating condition. The flooded type is always completely filled with liquid refrigerant, the liquid level being maintained with a float valve or some other liquid level control (Fig 9.1). The vapor accumulating from the boiling action of the refrigerant is drawn off the top by the action of the compressor. The principal advantage of the flooded evaporator is that the inside surf ace of the evaporator is always completely wetted with liquid, a condition that produces a very high rate of heat transfer. The principal disadvantage of the flooded evaporator is that it is usually bulky and requires a relatively large refrigerant charge. Liquid refrigerant is fed into the dry-expansion evaporator by an expansion device which meters the liquid into the evaporator at a rate such that all the liquid is vaporized by the time it reaches the end of the evaporator coil (Fig. 9.2). For either type, the rate at which the liquid is fed into the evaporator depends upon the rate of vaporization and increases or decreases as the heat load on the evaporator increases or de­creases. However, whereas the flooded type is always completely filled with liquid, the amount of liquid present in the dry-expansion evaporator will vary with the load on the evaporator. When the load on the evaporator is light, the amount of liquid in the evaporator is small. As the load on the evaporator increases, the amount of liquid in the evaporator increases to accommodate the greater load. Thus, for the dry-expansion evaporator, the amount of liquid-wetted surface and, therefore, the evaporator efficiency, is greatest when the load is greatest.

 

Fig. 9.1. Flooded evaporator. Notice accumulator and float control. Circulation of the refrigerant through the coil is by gravity. The vapor accumulated from the boiling action in the coil escapes to the top of the accumulator and is drawn off by the suction of the compressor.   Fig. 9.2. Dry-expansion evaporator. Liquid refrigerant vaporizes progressively as it flows through coil and leaves coil as a vapor. Feeler bulb controls rate of flow through the orifice of the flow control.

Answer the questions:

1. What is called an evaporator?

2. What categories do evaporators fall in?

3. Can you describe the work of the flooded evaporator using Fig.9.1?

4. How does the flooded evaporator differ from the dry-expansion evaporator?

Lesson В.



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