Copper is _______than zinc.

Zinc is _______than copper.

Diesel is_______flammable than petrol.

Aviation fuel is_______than gasoline.

The factors that affect the movement of the pig inside the pipeline are elevation, friction and _______

Crude oil pipelines contains much _______ debris than gas pipelines.

The cups of the pigs are worn and need to be _______.

A gas pipeline offers ___________ resistance to pigs than a crude oil pipeline does.

Asphalt is the _______ part of crude oil.

Crude oil is practically _______ when taken from the ground.

Petrol engines are _______ economical than diesel engines.

Grease is _______ than engine oil.

A jet engine is _______ than a combustible engine.

To ___________ someone is to try to make him do something.

____________ refers to the ability to withstand abrasive ware, surface indentation or scratching.

__________ is the opposite of toughness.

Steel is ___________ than paper.

A ___________ can be used to cut metal.

If the operator is ____________, he must stop and wait for a signal.

The _________ displays the flow rate.

The engineer is protected from eye injury by safety ________.

Solar power is the most important __________ energy source.

Gasoline can be used to ___________ our cars.

Oil companies do their best to ___________ the environment.

_____________ are rules for how to do something.

_____________ is the quality of the metal to shine or gloss and be polished.

The technician first _____________ the nails sticking on the wood and then threw it in the garbage container.

A mobile telephone is __________ than a landline.

If I ___________ coffee, I will clean it.