Добавил:
Upload Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
English book.doc
Скачиваний:
10
Добавлен:
14.11.2019
Размер:
1.64 Mб
Скачать

The Grammar in Use Modals

1. Translate the following sentences paying attention to the Modal Verbs and their equivalents.

1) The designer can always improve the operation of these receivers. 2) He could use any transmitter for this system. 3) The scientists are able to construct a new device by using semiconductors. 4) We have to increase the current strength by decreasing the resistance of the current. 5) After finishing the experiment scientists will have to discuss the results. 6) The students didn’t have to analyze these data. 7) We may say that photoelectric properties of transistor are largely used in TV sets. 8) In order to see certain stars we must use a telescope.

2. Put the modal verbs into the:

a) Past Indefinite Tense

b) Future Indefinite Tense

1) Computers can replace people in dull routine work. 2) The program is the set of instructions that may also include data to be processed. 3) Computer-controlled robots must increase the productivity of industry. 4) They can help in making different decisions. 5) The pupils may work with computers at the lessons. 6) Electric pulses can move at the speed of light. 7) Storage devices must have capacities for the input, output data and programs and for intermediate results. 8) Business minicomputers can perform to 100 million operations per second. 9) In order to solve scientific problems researchers must deal with the language of science – mathematics. 10) Programmers must write application programs in a way that computers can understand.

3. Find sentences with modal verbs in the text Additional Text (for individual work)

Read and translate the text.

"Seeking" for Tracks

Before data blocks can be read or written, the read/write head mechanism must be moved to the correct track. The read/write head contains the coil that detects or induces magnetism. It is moved by a stepping motor that can align it accurately over a specific track. Movements of the read/write heads are, in computer terms, relatively slow – it can take a hundredth of a second to adjust the position of the read/write heads. (The operation of moving the heads to the required track is called "seeking"; details of disk performance commonly include information on "average seek times".) Once the head is aligned above the required track, it is still necessary for the spinning disk to bring the required block under the read/write head (the disk controller reads its control information from the blocks as they pass under the head and so "knows" when the required block is arriving). When the block arrives under the read/write head, the recorded 0/1 bit values can be read and copied to wherever else they are needed.

The read circuitry in the disk reassembles the bits into bytes. These then get transferred over the bus to main memory (or, sometimes, into a CPU register). Disks may have their own private cache memories. Again, these are "hidden" stores where commonly accessed data can be kept for faster access. A disk may have cache storage sufficient to hold the contents of a few disk blocks (i.e. several thousand bytes). As well as being sent across the bus to memory, all the bytes of a block being read can be stored in the local disk cache. If a program asks the disk to read a block of data that is in the cache, the disk unit doesn't need to seek for the data. The required bytes can be read from the cache and sent to main memory. Commonly, hard disks have several disk platters mounted on a single central spindle. There are read/write heads for each disk platter. Data can be recorded on both sides of the disk platters (though often the topmost and bottommost surfaces are unused). The read/write heads are all mounted on the same stepping motor mechanism and move together between the disk platters.

1. Divide the text into the logical parts and give a title to each one.

2. Put questions to the text.

3. Discuss it with your groupmates.

Unit 5

Text Study: Output Devices. Printers.

Additional Text: Disks and Tapes.

Grammar: Revision of the Module.

Соседние файлы в предмете [НЕСОРТИРОВАННОЕ]