I. . to be:
) ;
) - ;
) Continuous Tense;
) Passive Voice;
) .
:
| 1. The worlds first radio receiver was built by Popov. was Passive Voice 2. The spacing between repeaters isto be maximized. is to be Passive Voice 3. Television is rapidly developing into one of the most popular means of conveying information. is Continuous Tense 4. An electric circuit is a path along which an electric current flows. is - 5. Many scientific centers are in the East of our country. are | . . . , . . |
II. . to have;
) ;
) perfect Tense;
) . :
| 1. design electronic computers we had to pass from radio valves to transistors. had 2. All these systems have electronic components. have 3. We have tried different approaches to overcome these difficulties. have Perfect Tense | - , . . , . |
III. . to do:
) ;
) ;
) ;
) .
:
| 1. Do you study the fundamentals of TV transmission? Yes, we do. Do ; do 2. Radio communication does play an important part in our life. does 3. Engineers did much to make space flights possible. did | -? . . , . |
|
|
|
IV. . , ing:
) ;
) ;
) , Continuous;
) .
:
| 1. Since electrical telegraph communication began in 1837, there have been developed many machines using various codes. using 2. Passing through a conductor the current heats it. passing 3. This is a sorting machine which can be used for parcel sorting. sorting sorting 4. The scope of research is growing year after year. growing , Continuous | , 1837 - , - , - . -, . , - . . |
V. . , -ed: Past indefinite :
) , ;
) , ;
) , ;
) , ;
) .
:
| 1. These experiments provided data necessary for the completion of our research. provided 2. The unusual state of matter at very low temperatures was called superconductivity. called , 3. The modulated signals, emitted by the transmitting aerial as electromagnetic waves, propagate in space with the speed of light. modulated , emitted , 4. They used instruments of improved design. used improved , | . . , - , . - . |
VI. . : ?
TELEPHOHY
Telephony is a branch of telecommunications which provides for the exchange of information in the form of speech. In any telephone system speech or other sounds are converted into electric signals that are transmitted to a distant point where they are converted back into reproduction of the original sound. A telephone set is an assembly of apparatus provided at each end of a telephone circuit to enable the user to make and receive calls. A microphone forming part of a telephone set is called a telephone transmitter while a transducer forming part of a telephone set and used to convert voice-frequency currents into audible sounds is a telephone receiver. The system also includes an electric bell responsive to low-frequency alternating current and is used as a calling device at a telephone station.
|
|
|
Telephony is widely used in everyday life. By means of a telephone people communicate with each other over a distance of thousands of kilometers. Telephony enables us to transmit sound energy over long distances.
| A telephone transmitter is a microphone forming part of a telephone set. A telephone receiver forming part of a telephone set and used to convert voice-frequency currents into audible sounds is a telephone transducer. | , . , - . |
