Exercise 3. Bead the first sentence and complete the second one using Gerund. Make use of the prepositions and the word gro­ups given below.

The scientists have carried out the experiment in order to test the idea. They did it ...

1) without; in addition to; in spite of; instead of; in view of; by;

2) to install new equipment; to propose an explanation of their own; to collect more evidence for its support; to modify the model; to give up the idea; to establish the mechanism of the process; to join the efforts of two laboratories; to encoun­ter difficulties with conventional equipment; to put to use a recent discovery; to make use of a new principle; to modify a conventional device.

Exercise 4. Transform the following Gerund constructions in­to clauses as given in the model.

Model: История открытия радиоактивности начинается с того, что Анри Бекерель сообщил о своем открытии лучей неизвестной природы.

The story of radioactivity begins with Henry Bequerel's having reported, his discovery of rays of unknown nature. - The story of radioactivity begins with the fact that Henry Bequerel reported his discovery of rays of unknown nature.

1) Mendeleev's having established, a periodic lair of nature has entered his name into the history book of the world science. 2) Success in science often results from the scientist's confining his attention to one problem for many years. 3) The results of the experiment depended upon his having applied the proper tech­nique. 4) The idea of scientist's being responsible for most ills of the present day situation is unfortunately quite popular. 5)A brain-storming session consists in everybody's proposing as many and as wild ideas as possible without being concerned as to whether they are workable. 6) Immediate recognition of a discove­ry depends largely on its being made at a proper moment. 7) Sci­ence is sometimes humorously defined as a practice of the scien­tist's satisfying his curiosity at the expense of the government.

Exercise 5. Change the tine clauses into the on/in/after + Gerund and the if-clauses into the with + Gerund.

1) You cannot present your paper to the conference if you do not check it carefully. 2) After we had arranged, everything for the experiment we started to work. 3) Many factors become impor­tant when we consider this problem. 4) The work will not be completed if we do not sum up the results. 5) We obtained the desi­red information when we were analysing our data. 6) After he had compared some numerical data he could readily obtain new parameters. 7) We cannot obtain the desired information if we do not conduct additional series of experiments. 8) Various approaches are possible when we solve this problem. 9) After they had chan­ged the experimental condition they repeated the experiment. 10)We shall not start the experiment if we do not get all the neces­sary equipment. 11) Several factors should be considered when we evaluate the experimental results. 12) We cannot make progress in our research if we do not take into account the results of other observers.

UNIT 9. The Infinitive

Exercise 1. Identify the infinitives and translate the sen­tences into Russian.

1) To make a choice between these two alternatives is not an easy task. 2) To foresee what the future will be like requires analysis of the past experience. 3) To be able to forecast the future we must begin by a thorough analysis of the past course of events. 4) To speculate about the future is one of the most basic qualities of man. 5) To appreciate the accuracy of the da­ta refer to Table I on page 57. 6) То avoid, making mistakes is always very difficult, because, to begin with, to err is human. 7) To take correct measurements it is necessary to use accurately adjusted instruments. 8) To distinguish between cause and effect is sometimes difficult. 9) The new equipment is necessary to in­crease the accuracy of results. 10) To prove this law experimen­tally is very difficult.