Неличные формы английского глагола. Коптева Н.Ю. - 27 стр.

                    Classroom Work
                     THE INFINITIVE

                   Forms of the Infinitive
Exercise 1. Change the form of the Infinitive according to the
             time expression.
1. You must touch sphere A with the rubber ro. (at this moment)
2. The charge must exert a force. (the moment the rod touches the
   sphere)
3. The rod must be charged negatively. (before the experiment
   took place)
4. They are lucky to reproduce such a force. (in their last
   experiment)
5. He is sorry not to follow your example. (a little earlier)
6. I am sorry not to be given any good suggestion. (at the conference
   yesterday)
Exercise 2. Change the Infinitive form from Active into Passive.
1. You are to compare the two forces after the experiment takes
   place. Then: The two forces are…...
2. We must induce the charge without touching the body. Then:
   The charge must…...
3. Am I to remove the rod from the vicinity after B is moved
   away? Then: Is the rod…...
4. The action must leave both the spheres with their respective
   charges. Then: Both the spheres…...
5. It is clear that one is to compare the motion of electrons with
   the motion of electrons. Then: It is clear that the motion of
   electrons…...
6. Am I to bring the charged rod close to the metal sphere?
   Then: Is the charged rod…...
7. We must calculate the force exerted by either charge upon the
   other. Then: The force exerted by either charge upon the
   other…...
Exercise 3. Use thå Infinitive either Active îr Passive instead of
            thå Clause.
1. The ball which is to be lowered into the ðàil is charged
   negatively.

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