Используя диалог из упражнения 1, составьте монолог о машинах и механизмах. Постарайтесь употребить следующие фразы:
• This theme is significant because …
• I’d like to pay attention to … because …
• It is important to know that …
• It is interesting to know that …
• You should note that …
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• That means that …
• The definition of ... is the following …
Диалог
The lesson is devoted to the machines and mechanisms.
Teacher: Professor Robinson (Prof. Robinson).
in the bicycle. Note that the name of the working body indicates that
this part helps a person to perform the work for which the machine was
created to.
The purpose of the engine is to transform one form of energy into
another. In a car, motorcycle, tractor, energy of fuel is converted into
heat and then into mechanical motion. The engines of the vacuum
cleaner, washing machine turn the electrical energy into mechanical.
All engines, including electric motors, are heated during operation. This
means that part of the energy is converted into heat.
Student 2: But, Prof. Robinson, a bicycle does not have any engine.
Why is it called a machine?
Prof. Robinson: Good question! You see, the person performs the
role of the engine and spends his energy. That is why, it is a machine.
Student 2: Now, it’s clear for me. Thank you!
Prof. Robinson: Good! Now, let’s sum up. Machines are devices that
perform useful work for a person and at the same time turn one kind of
energy into another. The main parts of each machine are the working
body, engine, and mechanism. Mechanism is a device for converting one
kind of motion into another.
Thank you for attention. Revise the material “Machines and Mecha-
nisms” and be ready for the next lesson!

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