1.Electricity is used to produce heat.
2.Today plastics are being applied for car bodies.
3.The electric cars will be widely used in future.
4.He worked at the plant all his life.
5.The device is being tested now.
6.Engineering progress opens up wide prospects before man.
7.The alloys were experimented upon in our lab.
8.Having been repaired,the engine began operating better.
9.I had been tested the device for two hours when you came.
10.I have never been there before.