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Файл:English Grammar for Electrical Engineers. Учебное пособие
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operation of the divider. 8. The resistors dissipate some power in doing this job. 9.
Sometimes voltage division is required for biasing. 10. A resistor can keep the transistor
from using up a lot of power just getting hot. 11. This keeps the transmitter from
interfering with communications on the airwaves. 12. The transmitter output heats the
resistor without radiating any signal.
Ex. 2. Translate from Russian into English using the gerunds.
1. Нагрузочные резисторы, подключенные параллельно конденсаторам
сглаживающего фильтра, потребляют накопленный заряд конденсаторов, так что
обслуживание становится безопасным. 2. Здесь необходимо закоротить все
конденсаторы сглаживающего фильтра, используя отвертку с изолированной ручкой
и надев толстые, изолирующие перчатки, прежде чем работать с источником
постоянного тока. 3. Самый дешевый способ сделать резистор – это смешать
порошкообразный уголь (хороший проводник электричества) с некой непроводящей
субстанцией, заложить полученный похожий на глину материал в цилиндрическую
форму и вставить проволочные выводы с двух концов. 4. Этот вид резистора также
имеет следующие преимущества: он не имеет реактивной составляющей, что
означает, что он поставляет почти чистое напряжение в цепь, практически нет
ёмкостного сопротивления или индуктивности. 5. Теперь вы можете подсчитать
мощность резистора, используя формулу расчета мощности через ток и напряжение.
Ex. 3. Use Participle I, Participle II or the Gerund of the verb in brackets and
translate the sentences.
1. Solar energy has been converted to electricity by (use) solar cells, which are
semiconductor devices (produce) from thin slices of silicon. 2. The (apply) technique
brought about quite unexpected results. 3. (Cool) an electric conductor results in its
resistance to electric current. 4. Is any metal capable of (draw) out into a wire? 5. A
constant speed of the device is maintained by (supply) it with energy. 6. Steam is an
important factor in producing usable energy because of the power (create) by its
expansion. 7. On (lose) some of its electrons, the atom has a positive charge. 8. The
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supplies (require) include metal conduits, boxes, fuses, and other elements. 9. Switch
Active
Passive
Indefinite
to do
to be done
Continuous
to be doing
-
Perfect
to have done
to have been done
Perfect continuous
to have been doing
-
board is an assemblage of (control) and (indicate) devices mounted upon a frame. 10. Mica
is used as a dielectric due to (have) high voltage strength.
3.8.3 The Infinitive. Infinitive constructions
The infinitive is a verbal form (a non-finite verb form) which consists of the base
form of the verb with the particle “to”: to do; to work; to recharge; etc. The infinitive has
some properties of the verb. The infinitive names an action (to recharge batteries) or state
(to be aware), but cannot show person, number, or mood. The infinitive has active and
passive forms (to take; to be taken) and can express voice and time, though in a rather
limited way. The infinitive has some properties of the noun and can be used in the function
of the subject or of an object.
Use of particle “to”. As a rule, the infinitive is preceded by the particle “to”. The
particle “to” is omitted after modal verbs, after the verbs “make, let”, after the verb “help”
in American English, and in constructions like “She saw him work; He heard the machine
stop”. If the verbs “make, help, see, hear” in such constructions are used in the passive
voice, the infinitive after them keeps the particle “to”: He was seen to work. The machine
was heard to stop.
Forms of the Infinitive
The infinitive can express time only relatively, i.e. in relation to the action expressed
by the verb in the predicate. The action indicated by the infinitive can be simultaneous
with the action expressed by the verb in the predicate, or it can precede the action
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expressed by the verb in the predicate. The forms are limited in the verbs which cannot be
used in the passive voice forms.
The constructions “verb + object + infinitive”. The infinitive functions as an object
in such constructions and always stands after another object expressed by a noun or a
pronoun. These constructions may be grouped as: 1) the infinitive is used after the verbs
“advise, allow, ask, beg, convince, encourage, forbid, force, help, hire, instruct, invite, let,
make, order, permit, persuade, remind, teach, tell, urge, warn”. The infinitive is used
without the particle “to” after the verbs “make, let” (and “help” in AmE); 2) the infinitive
is used after the verbs “want, would like, require, rely on, count on, expect, consider,
find”; 3) the infinitive without “to” is used after the verbs of sense perception “hear, see,
watch, observe, notice, feel”; 4) the infinitive is used without the particle “to” after “have”,
but with “to” after “get” with the causative meaning, i.e., “have” and “get” here generally
mean “induce someone to do something; ensure that someone does something” (“have” is
close in meaning to “ask” and “get” close in meaning to “persuade”).
Exercises
Ex. 1. Use the infinitive in brackets with or without particle “to”.
1. In theory, a resistor can … (to have) any ohmic value from the lowest possible
(such as a shaft of solid silver) to the highest (dry air). In practice, it is unusual … (to find)
resistors with values less than about 0.1Ω or more than about 100 MΩ. 2. This means that
the resistance might … (to be) as much as 10 percent more or10 percent less than the
indicated amount. 3. You might … (to measure) the value of a 470-Ω resistor and … (to
find) it … (to be) 427 Ω. 4. You should … (to recall) that formula. 5. A good engineer
never tries … (to take advantage) of this and … (to use). 6. There are various ways … (to
approach) problems of resistors changing value when they get hot. 7. One method is … (to
use) specially manufactured resistors that do not appreciably …(to change) value when
they get hot. 8. This will … (to keep) the resistor from getting very hot. 9. It is unwise …
(to combine) resistors with different values. 10. This can sometimes … (to work), but in
practice it’s difficult … (to find) a pair of resistances that will … (to do) this job just right.
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Ex. 2. What forms of infinitives are used in the infinitive complexes given below
– complex subject or complex object? Translate the sentences into Russian.
1. The line appeared to be demagnetized. 2. We consider the current to be the
amount of electrons flowing past a point every second. 3. Nuclear plants are expected to
be located away from urban areas. 4. The capacity of generating units was said to have
been doubled. 5. The output of machinery is known to be steadily increasing all over the
world. 6. Ebonite, rubber, and glass are considered to be good insulators. 7. In some
countries, the nuclear power plants are believed to produce about 80 per cent of the whole
amount of energy. 8. What two conditions are necessary to cause an electric current to
flow? 9. The use of underground transmission lines is known to have been increased. 10.
By 1959, maximum transmission voltages were proclaimed to have been increased to
345,000 volts.
Ex. 3. Translate the sentences into English using the complex object
construction.
1. Обычно можно услышать, как ученые называют эти единицы «тесла». 2.
Когда вы слышите, как кто-то говорит, что такой-то и такой-то трансформатор
имеет определенный коэффициент преобразования, убедитесь, какой вид
преобразования имеется в виду. 3. Вы можете иногда видеть, как
автотрансформаторы работают в радиоприемниках или передатчиках. 4. Бортовой
компьютер видит, как очертания острова постоянно меняются. 5. Двухсигнальный
электронно-лучевой осциллограф позволяет вам наблюдать две формы сигнала в
одно и то же время. 6. Так называемая смонтированная в стойку хай-фай система
экономит пространство и позволяет системе выглядеть профессиональной. 7. В этом
случае вы не сможете «заставить» ток идти по цепи. 8. Это магнитное поле
достаточной силы, чтобы заставить их двигаться. 9. Я хочу, чтобы вы вычислили эту
функцию. 10. При какой частоте мы можем ожидать, что сигнал возникнет на
выходе?
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3.9 The conditional sentences
A conditional sentence is a complex sentence with a subordinate clause of
condition that usually begins with the conjunction ‘if’. The clause of condition (the ifclause) indicates the conditions under which the action in the main clause may be realized.
Conditional sentences are usually divided into three main types: 1. structures with
real condition (first type of conditional sentences, or first conditional); 2. structures with
unreal condition referring to the present or future (second type of conditional sentences, or
second conditional); 3. structures with unreal condition referring to the past (third type of
conditional sentences, or third conditional).
Conditional sentences with real condition express real, true to fact / factual
conditions under which the action in the main clause can be realized. The tenses of the
indicative mood are used. Note that the future tense with the verb ‘will’ is not allowed
after ‘if’ in clauses of condition. The future idea is usually expressed by the simple present
in the if-clause of condition, e.g.: If a magnet is brought near another magnet, the force
will be either repulsive or attractive, depending on the way the magnets are oriented.
Supposition in English is expressed with the help of the past tense forms, usually by
the verbs ‘would, should, could, might’. Conditional sentences with unreal condition in the
subordinate clause of condition (if-clause) express hypothetical, unlikely, improbable,
unreal, contrary to fact conditions under which the action in the main clause might be
realized or might have been realized. The forms in the subjunctive mood are used.
In the second type of conditional sentences, to show unreal condition in the present
or future, the verb in the subordinate clause (i.e., where the condition is stated) is used in
the same form as the simple past tense (e.g., knew, wanted). The construction ‘would +
simple infinitive (without “to”) is used in the main clause. In speech, ‘would’ may be
contracted to“ ‘d ”, e.g.: If a magnet were brought near another magnet, the force would be
either repulsive or attractive.
NB: the verb “to be” in the if-clauses with unreal condition referring to the present
or future is used in the form ‘were’ for all persons, e.g.: This would happen, for example,
if a 200-V dc source were connected in series with the output of a common utility ac
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outlet, which has peak voltages of approximately ± 165 V. The form ‘was’ may be used in
informal everyday speech for the first and third person in the singular, especially in British
English.
In the third type of conditional sentences the situation refers to the past, the time is
gone, and there is no possibility of realizing the indicated condition and the action that
depends on this condition because they are already in the past. Thus, the condition
indicated in the if-clause is unrealizable, unreal, and contrary to fact. To show unreal
condition in the past, the verb in the subordinate clause (i.e., in the part where the
condition is stated) is used in the same form as the past perfect (e.g., had known, had
wanted). The construction would + perfect infinitive (i.e., would + have + past participle)
is used in the main clause. ‘Had’ and ‘would’ may be contracted to “ ‘d ” in speech, e.g.:
If a magnet had been brought near another magnet, the force would have been either
repulsive or attractive.
Exercises
Ex. 1. Put the following sentences into different conditional forms.
1. If the cost … (to be brought) within reason, Edison … (to be vindicated). 2. If two
perfect sine waves … (to have) the same frequency and the same amplitude, but are in
opposite phase, the composite wave … (to have) zero amplitude. 3. If two perfect sine
waves … (to have) the same frequency and the same phase, the composite wave … (to be)
a sine wave with an amplitude equal to the sum of the amplitudes of the two original
waves. 4. If a 175-V dc source … (to be connected) in series with the utility mains from a
standard wall outlet, the result … (to be) fluctuating dc. 5. If the wire … (to be short), the
current … (to begin) to flow immediately, and it … (to attain) a level limited by the
resistance in the wire and in the battery. 6. If a coil having a certain number of turns and a
certain diameter … (to be “stretched out”), its inductance … (to decrease). 7. If there …
(to be) no mutual inductance among two or more parallel-connected inductors, their values
… (to add up) like the values of resistors in parallel. 8. If there … (to be) several inductors
in parallel, and one of them … (to have) a value that is much smaller than the values of all
the others, then the total inductance … (to be) a little smaller than the value of the smallest
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inductor. 9. If the coil … (to carry) more than a certain amount of current, the core … (to
saturate). 10. If the plates … (to be) small, they … both (to become) charged almost
instantly, attaining a relative voltage equal to the voltage of the battery. 11. If five 0.050µF capacitors … (to be connected) in parallel, what … the net capacitance … (to be) of the
combination? 12. If you (to understand) these fundamentals and (to apply) them to current
technology, it (take) much less effort to stay on top of this changing industry. 13. Even if
the current (not to pass) directly through your heart, it (to contract) the muscles in your
chest and (to asphyxiate) you. 14. If you (to understand) how electricity behaves and
respect its potential for danger, then you (to minimize) the dangers and (to work) in
relative safety. 15. If you (to take) your side cutters and (to cut) a small strand of copper
from a cable, you (to have) billions of copper atoms.
Ex. 2. Continue the sentences according to the rules of forming conditional
sentences.
1. If the two ac waves (and thus the magnetic fields they produce) are in phase, … .
2. If the two waves are in opposing phase,… . 3. If two equal-valued inductors are
connected in series so their fluxes oppose (or buck each other) and k = 1,… . 4. If the main
objective is to get a large inductance in a small space, … .5. If the same two inductors (33
mH and 55 mH) are connected in parallel without mutual inductance,… . 6. If the coil
fields reinforce each other,… . 7. If the coil fields oppose in the foregoing seriesconnected arrangement, assuming the coefficient of coupling does not change,… . 8. If
these two sheets of metal are connected to the terminals of a battery,… . 9. If two or more
capacitors are connected in series, and one of them has a value that is tiny compared with
the values of all the others,… . 10. If two or more capacitors are connected in parallel, and
one of the capacitances is far larger than any of the others,… . 11. If the temperature is
below freezing, … .12. If the distance between the two charges is doubled, …… 13. If
another external force, like a voltage, is applied, …….. 14. If there is a break in a closed
circuit that prevents the flow of electricity…….15. If you want to find out how much
energy a particular device is using,…..
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3.10 The subjunctive mood
Mood shows how the action is viewed by the speaker; that is, whether the action is
regarded as a fact, as a command, as a supposition, or the like. The indicative mood
expresses a real action in the present, past, or future. The imperative mood expresses a
command or request. The subjunctive mood expresses a hypothetical, suppositional action.
The subjunctive mood is represented by subjunctive I, II, III, IV. Subjunctive I is
considered to be obsolete and rarely used in everyday speech, it may be found in official
documents or poetry, e.g.: Let it be! Suffice it to say!
Subjunctive II is found in subordinate clauses of conditional sentences of the second
and third types. This form is also used in object clauses after ‘I wish’, e.g.: I wish I
recharged the batteries in time. I wish I had recharged the batteries in time.
Subjunctive III is found in principal clauses of conditional sentences of the second
and third types (would + certain form of the Infinitive).
Subjunctive IV is used to express (and emphasize) urgency, importance, desirability,
demand, order, suggestion, request by means of “should + Infinitive”. It is used in subject
subordinate clauses in sentences with the formal subject “It” after “it is necessary that; it is
important that; it is imperative that; it is crucial that; it is vital that; it is essential that; it is
urgent that; it is required that; it is advisable that; it is desirable that” and after other
similar expressions. It is also used in object subordinate clauses after “demand that; order
that; command that; urge that; insist that; advise that; recommend that; suggest that;
propose that; request that; ask that; beg that”. It is also used to express regret, annoyance,
surprise after “I am sorry that; I regret that; I am surprised that; it is surprising that; it is
strange that; it is annoying that”, and also in special questions after “why” to express
strong surprise, e.g.: Why should I do it?
The construction ‘should + Infinitive’ are also used in subordinate clauses of
purpose after “lest”, a rather bookish conjunction. The conjunction “so that” is much more
common in subordinate clauses of purpose than “lest”. Clauses of purpose with “so that”
are generally used in the indicative mood, usually with the modal verbs “can, could, may,
might”.
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Exercises
Ex. 1. Read the following sentences, containing the subjunctive mood forms.
Which of the sentences refer to the present (the future) and which to the past?
Translate the sentences into Russian.
1. Without the Sun there would be no light, no heat, no energy of any kind. 2.
People would appear to magically fly through the air when they were swimming, and
ocean waves would appear to be unexplainable forces that could knock you over at
seemingly random times. 3. In fact, without magnetism, there would be no electricity at
all. 4. Oxygen is an element of greatest importance to the Earth as all living things would
die without it. 5. If it were not for lasers a great number of technological developments
would not have taken place. 6. No subject is more surprising than magnetism; what would
you think if you found that on mixing ebonite and Bakelite in some definite proportions a
good conductor is formed or that a mixture of copper and iron forms a good insulator? 7. If
we could see the lines of flux of that electromagnetic field, we would see concentric rings
around the current-carrying conductor falling off in strength as they get farther from the
conductor. 8. But if we were to touch a live wire with alternating current, we would
instantly recognize that the average value over a cycle doesn’t convey enough information.
9. Despite Edison’s rebuff, Tesla continued working for him, hoping that one day he
would have a chance to realize his polyphase AC system. 10. The study of electricity and
power distribution would be incomplete without understanding certain circuit elements,
such as resistors, inductors, capacitors, and transformers, and the way they behave,
combine, and interact.
Ex. 2. Complete the sentences using necessary forms of the subjunctive mood.
1) It’s a pity you don’t use the offered diagrams. If I were you … .
2) Why didn’t you use the scheme I gave you? In your place… .
3) The device looks dangerous as if… .
4) We mustn’t use this resistor. I suggest… .
5) “Suppose a resistor, a coil, and a capacitor are in parallel,” the teacher told the
students. “It’s necessary… .”
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6) Almost all factories in Russia have sewage-purification facilities now so that
… .
7) The technical director insists … .
8) I didn’t know that this digital showroom was so interesting. If I had known
this, … .
9) If I had more time, … .
10) If I were you, … .
11) If there had been witnesses of the incident, … .
12) Had I lived in the 19th century, … .
13) If Marie Curie had not died so young, … .
14) …, I’d calculate the inductive susceptance.
15) …, I’d calculate the capacitive susceptance.
16) …, they would short out all filter capacitors.
17) …, a circuit would have occupied and used all the electricity.
18) …, you would be technically right.
Ex. 3. Illustrate different meanings conveyed by the suppositional mood
(subjunctive IV).
1) Suggestion, recommendation, advisability, importance, necessity:
it is advisable…
it is recommended…
it is suggested…, etc.
I think it’s necessary……that smb. should do smth.
I think it’s important……that smb. should do smth.
I think it’s advisable ……that smb. should do smth.
I suggest…
I recommend…
I advise …
2) Order, command, demand:
it is (was, will be) ordered (commanded, demanded) that smb. should do smth.
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