Б. Инфинитив в функции определения

The problem to be solved; the work to be finished; the cards to be punched; calculations to be performed; the machine to be shown at the exhibition; the device to be provided with the necessary facts; computers to be used for data processing; efforts to increase reliability; electronics to connect systems and subsystems; the speed of response to depend on the size of transistor; computers to perform thousands of calculations per second; vacuum tubes to control and amplify electric signals; these are circuits to use a large number of transistors; operations to be performed.

Exercise 5.Составьте предложения, используя инфинитив.

Model:Graph plotters use pens. The purpose is to produce images. (Графические плоттеры используют перья. Цель – создавать изображения.)

=> Graph plotters use pens to produce images (Графические плоттеры используют перья, чтобы создавать изображения).

1.Input devices are used. The purpose is to get the data into the computer. 2. Computers can interact with pupils. The purpose is to enhance the learning process. 3. We can use speech recognition. The purpose is to dictate data into the computer. 4. Computers are used. The purpose is to diagnose many illnesses. 5. The purpose is to send your e-mail. Click the Send button. 6. The purpose is to create a database in Excel. You have to remember the following. 7. Use the online help. The purpose is to find out how to create a database. 8. The purpose is to work effectively with desktop publishing packages. You need a computer with high specification. 9. The mouse is moved around on the desk. The purpose is to transmit the movement of your hand to the computer. 10. A spellchecker is very useful. The purpose is to avoid mistakes. 11. The hard disk is surrounded with a metal case. The purpose is to prevent all outside substances from entering the disk area. 12. Light pens need special software. The purpose is to make them work.

Exercise 6.Read the text. Find modal verbs and verbs in Passive voice as much as possible.

As it is well known, a computer cannot perform or complete any useful work unless it is able to communicate with its exter­nal environment. All data and instructions enter and leave the central processing unit through primary storage. Input-output devices are needed to link primary storage to the environment, which is external to the computer system. So input devices are used to enter data into primary storage. Output units accept data from primary storage to provide users with information or to record the data on a secondary storage device. Some devices are used for both the input and output functions.

The data with which these devices work may or may not be in a form that humans can understand. For example the data that a data entry operator keys into the memory of a computer by typing on a keyboard are readable by humans. However, the data that tell a computer about the performance of an automo­bile engine are not in a form that humans can read. They are electrical signals from an analog sensor. Similarly, output may be on a printed page, which humans can read easily, or upon some other medium where the data are not visible, such as on magnetic tape or disk.

As we know, all of the data flow from input to final output is managed by the control unit in the CPU. Regardless of the na­ture of the I/O devices, special processors are called I/O interfaces.

Exercise 7.Get ready to speak about I/O environment (10-15 sentences).