|
Читайте также: |
1. Nick (think) that his father (not yet come) home.
2. Mary (tell) us that she (cook) a good dinner.
3. The car (go) when I (look) into the street.
4. The patient (already die) by the time I (see) her.
5. Look! Kate (wash) all the dishes.
6. Your mother (return) from work? Can I speak to her?
7. She (clean) her flat the whole day on Sunday.
8. All the garages (close) by the time we (cross) the border.
9. They cook the whole day yesterday.
10.She is very happy. Her son (finish) school.
7. Translate the following sentences into English .
1. Шум розбудив дітей, що спали наверху.
2. Перед тим, як лягти спати, вона півгодини дивилась телевізор.
3. Що ти робила вчора цілий день – Я писала доповідь з 10 до 12 години.
4. Я писала доповідь більше години, коли прийшли мої друзі і допомогли мені.
5. Коли ви закінчили цю роботу?
6. Вчора, коли ми повернулися з вечірки діти вже спали.
7. Вона приїхала в наше місто п`ять років тому. До того часу вона вже закінчилиа університет.
8. Ми сидемо тут вже більше години, а він і досі не повернувся.
9. Я й досі в`яжу цей светр. Я в`яжу його вже півроку.
10. Я ніколи не бачив цунамі, поки не поїхав до Японії.
Rewrite these sentences in passive keeping them in the right tense.
1. We have invited all the students in the school.
2. Someone has moved my chair!
3. The police are questioning Mr and Mrs Davidson.
4. They will send us a box of fruit.
5. They had written the composition before the bell rang.
6. They look after the children.
7. We shall do the translation in the evening.
8. They speak English there.
9. They will stage this play at the beginning of the next season.
10. They have forgotten the story.
Make the following sentences passive.
1. You must listen to your teacher very attentively.
2. You should not insist on it.
3. Chief is sending Nick to Moscow next week.
4. They supply students with textbooks.
5. We must do this work very carefully.
6. Sorry about the noise – They are mending the road.
7. This company has built a new cinema in our town.
8. He will finish his new book next year.
9. They sell flowers in shops and in the streets.
10. The owner of the Cafe Royal has turned it into a casino.
Translate the following sentences into English.
1. Учитель сказав, що наші диктанти перевірені.
2. За дітьми доглянуть.
3. Листи відправляють щодня.
4. Цю книгу дуже часто запитують в книгарнях.
5. Цей кінотеатр був збудований до того, як ми приїхали сюди.
6. Мою подругу щороку відправляють за кордон.
7. Руки слід мити перед кожним прийомом їжи.
8. Дитині треба давати фрукти.
9. Собаку можна годувати м`ясом і овочами.
10. Коли виправили помилку?
III семестр
Варіант №10
Read and translate the text.
CENTRIFUGAL PUMPS.
DEFINITIONS
The centrifugal pump is so called because the pressure increase within its rotor due to centrifugal action is an important factor in its operation. In brief, it consists of an impeller rotating within a case. Fluid enters the impeller in the center portion, called the eye, flows outwardly, and is discharged around the entire circumference into a casing. During flow through the rotating impeller the fluid receives energy from the vanes, resulting in an increase in both pressure and absolute velocity. Since a large part of the energy of the fluid leaving the impeller is kinetic, it is necessary to reduce the absolute velocity and transform the large portion of this velocity head into pressure head. This is accomplished in the volute casing surrounding the impeller or in the flow through the diffuser vanes.
The demand for greater capacity, without increasing the diameter to obtain it, resulted in an increase in the dimensions parallel to the shaft. This in turn required an increase in the eye diameter to accommodate the larger flow am corresponding change in the vanes at entrance, resulting in the mixed-flow impeller whose specific speed is higher than that of a radial-flow impeller.
A still further increase in specific speed is obtained with the propeller axial-flow pump. In this type there is no change in radius of a given streamline, and hence centrifugal action plays no part.
| Rotor | ротор, робоче колесо насоса |
| Impeller | насосне колесо |
| Rotating | обертання |
| Case | корпус |
| Outwardly | назовні |
| Circumference | коло, довжина кола |
| Vane | лопать, лопатка |
| Velocity head | швидкісний напір |
| Pressure head | гідростатичний напір |
| Axial-flow pump | осьовий насос |
| Volute casing | спіральний кожух |
| Diffuser vane | дифузна лопатка |
2. Comprehension check .
1. What does the centrifugal pump consist of?
2. How does the centrifugal pump work?
3. What is it necessary to do when a large part of the energy of the fluid leaving the impeller is kinetic?
4. What did the demand for greater capacity result in?
5. What is the function of the propeller or axial-flow pump?
Дата добавления: 2015-11-16; просмотров: 56 | Нарушение авторских прав
| <== предыдущая страница | | | следующая страница ==> |
| Compressors in refrigeration and air conditioning (part II) | | | Put the following into indirect speech. |