Английский язык. Ч.3 (Units 9,10). Ильичева Н.А - 46 стр.

f) Spaceships would not be able to travel at a speed close to the speed of light
   because too much energy would be needed. It would be impossible to
   overcome enormous practical problems.


Grammar in use


17. Read the sentences and identify the type of conditionals.
1. This energy can be destructive if it impinges on living tissue.
2. If heat flew spontaneously from a colder object to a hotter one, it would be
   like a ball rolling up a hill on its own accord.
3. If an object travels with a constant speed in a straight line, then it also has a
   constant velocity.
4. If the casing of the appliance had been connected to ground, the man wouldn’t
   have received an electrical shock.
5. If you throw a rock straight up into the air, it will rise for a while, but
   eventually acceleration due to the planet’s gravity will make it start to fall
   down again.
6. If you add equal amounts of heat to equal masses of iron and aluminium, the
   temperature of iron will increase by 100 °C and the temperature change in
   aluminium will be only 48°.
7. If the air of the troposphere were static, there would be little change in the
   local atmosphere conditions that constitute the weather.
8. If Alexander Fleming hadn’t noticed the mould in one of his glass dishes, he
   would never have discovered penicillin.
9. Should a plugged in radio happen to fall into the bathtub, then the whole tub
   including the person in it, may be plugged into 110 V.
10. Should you be caught outside during a thunderstorm, seek shelter in a
   building. If no buildings are available, seek protection in a ditch or ravine.


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