, , , , :
1. find the mass of the electron was then of prime
importance.
2. To be fully effective control must start with the
production of raw materials.
3. To explain the pressure of gases and their diffusion,
it is generally supposed that all substances are made of very
minute particles called molecules.
4. As regards electron spin, Dirac has shown that to
postulate rotational attributes for the electron does not
involve the induction of any additional hypothesis concerning
the nature of the elementary particle.
5. ( be + )
- be. be Indefinite Perfect. . , : aim , intention .
be , (), , :
Our aim is to master English.
, . ( ...)
. , - (. . 19).
, be + :
aim object
action plan
approach problem ,
concern , procedure
effect purpose
function manner
intention method ,
step technique
task way
. , - be. :
1. One way of obtaining hydrogen is to pass electric
current through water.
2. Our present concern will be to discuss the information
obtained during the flight.
3. The method in use is to smash up the simplest nuclei.
4. The purpose in mind is to get a catalyst to speed up
the reaction.
5. The problem has been to solidify the substance under
investigation.
6. The difficulty will be to obtain the substance in question.
6. (be + )
be , , . Present Past Indefinite, :
1) This experiment is to show the dependence of
temperature on solubility.
.
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... ...
2) This substance is rarely to be found free in nature.
.
1. , ( if ) ( when ) be :
If the substance is to be used in the experiment, it should be pure. , .
...
It is necessary to use a catalyst, if a reaction is to proceed more rapidly.
, ( , ).
2. - It is to be noted (, ) .
3. be about . be Present Indefinite, , , , -; be Past Indefinite, , ( ), , .
The substance is about to catch fire. . The substance was about to catch fire. .
, be + :
to anticipate ; ( )
to emphasize
to expect
to note
to point out
I
, - be:
1. This element is to be found free in nature.
2. We are to study the main laws of physics.
3. In our experiment we were to compare the two gases.
4. Some more heating is to produce the effect required.
5. New sources of cheap energy are to be found.
II
(. 2):
6. It is to be expected that those elements will unite.
7. It is to be noted that...
8. It is to be anticipated that...
9. It is to be emphasized that...
10. It is to be understood that...
11. It is to be remembered that...
III
. call attention to, make mention of:
12. Care is to be taken not to overheat the substance.
13. Steps are to be taken to purify the substance.
14. Account is to be taken of the high boiling point of
this liquid.
15. Use is to be made of the data obtained.
IV
, 1:
16. If fuels are to be burned efficiently it is necessary to
mix air with the fuel, before it is burned.
17. If water gas is to be used as a source of pure
hydrogen, carbon monoxide must be used.
18. When a substance is to be prepared on a commercial
scale the method chosen must utilize unexpensive and readily
available materials.
19. Sulphuric acid when it is to be diluted with water,
must always be poured gradually into an excess of water.
V
, 3:
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20. The melt is about to crystalize.
21. Helium was about to liquify.
.22. The band theory which we are about to discuss makes rather useful statements.
VI
:
23. It is to be noted that at ordinary temperature this
substance dissolves only slightly.
24. We are to take advantage of the high penetrating
power of these rays.
25. Little or no oxygen is to be found there.
26. As a matter of fact no living beings are to be expected
on Venus.
27. It is a matter of common observation that bodies are
to be cooled to get them solidified.
28. It is to be emphasized that the electrical conductivity
of beryllium is by no means as great as was formerly assumed.
29. Water is to be purified to meet our needs.
30. You are to take into consideration that apart from
kinetic evidence there is little direct proof of the production
of free oxygen atoms by photolysis of any oxide.
