6) The mother was told not to worry about her sick boy as he was out of danger.
They will bale published the book by August.a) The book will have been published by August.
This book ... in New York last year. a) was published;
This camera ... in Japan. 6) is made;
This department store ... this year, let's go shopping there. r) has been built;.
This portrait. .. by a talented painter last year. б) was painted;
This suit looks shabby. Sure. I have already worn it for three months.
a) This suit looks shabby. Sure, it bas already been. worn for three months.
Usually breakfast here ... at 8 o'clock. б) is served;
We haven't discussed the book yet, let's do it now .
в) The book hasn't been discussed yet, let's do it now.
We were so glad to find out that they had taken 50 our students to the international conference.
г) We were so glad to find out that 50 our students had been taken to the international conference.
We will learn the results of the game when they ... on the radio. a) are announced;
We will send you this report as soon as we have fixed all the dates finally.
a) Wc' will send you this report as soon as all the dates have been fixed finally,
Well have repaired your TV by the end of the week.
a) Your TV will have been repaired by the end of the week.
When I went into the cinema, they were showing the film.
r) When I went into the cinema, the film was being shown.
A building which houses a ... is called a power or,generaling station. г) turbo-generator
A dynamo a ... that nakes electricity when it is made to rotate ai higli speed. в) machine
A great natural source of electricity is ... д) lightning
A high-tension battery is made up of a number of small batteries connected in ....r) series
A major development in the electronic industry has been the replacement of thermionic valves by ... .
a) transistors
A rectifier is sometimes called a .... в) diode
A relay consists of an electro-magnet which, when energized, attracts a soft ... armature. д) iron
A remote control may be brought about by the use of a ... . г) relay
A simple b,.ltery convt-its chemical energy into ... energy. г) electrical
A simple diode consists of a ... that has only two electrodes: anode and cathode. г) valve;
A simple thermionic valve is called a ..- because it has two electrodes. 6)diode
A station that uses the power of falling water is known as a ... station. д) hydroelectric
A step-down ... reduces the input voltage. д) transformer
A switch is used in almost every piece of electrical... . д) apparatus
A tetrode lias four. an a pentode five .... д) electrodes
A transistor is a ... . г) semiconductor
A transistor lias three electrodes, a base. an .... and a collector. д) emitter
A transistorized circuit is simpler, smaller, and ... stronger. 6) technically
A transformer is a static ..., it has no moving parts. a) machine
A unit of resistance is called an .. a) ohm
A unit of power is ... . д) watt
A unit of power is ... . д) watt
A valve is a ... that allows a flow in one direction only. д) device
Alternating ... is the kind of electricity that is generated in power stations for domestic and industrial use, the direction of flow
changes very quickly. г) current
Amber is a fossil resin. ... in colour а) yellowish
An electric current is the ... of electrons. б) How
Any material that will not permit the flow of electricity is known as an .... г) insulator
Any material that will allow electricity to flow through it is called a ... . 6) conductor
A ... changes alternating cui-rent to direct current. 6) rectifier
A ...consists of two coits of wire that are wound around a soft iron core. 6) iranslbrmer
A ... is a valve with three electrodes, an anode, a cathode and a control grid. г) triode
A ... is used to increase or decrease the voltage of an electric power supply. д) transformer
Common ... materials include air, oil. glass, porcelain, mica, rubber and plastics. a)insulating
Current, voltage and resistance bear a definite ... to one another. г) relationship
…can be very dangerous if it is carelessly used. в) electricity
…current is the kind of electricity we get from a battery, the flow of current is in one direction only.