Four-stroke engine

The process of compressing fuel and air

A force caused by pushing against something

An opening where spent fuel is released

To make something burn or catch fire

The process of releasing spent fuel

The four-stroke engine works by heating fuel and air in a...

During the first stroke the ............. valve lets fuel and air into the cylinder.

The intake valve closes during the ............. stroke.

The mixture of air and fuel ................. during the power stroke.

The final stroke ....................... gas.