How combustion engines work

Do you know how a car engine works? You'll find that out in this Youtube video:




Here you can listen and complete the script with the words provided:

appropriately
downward
drive
expel
hood
intake
known
operates
reverses
rotary
spark


While the internal combustion engine under the _______(1) of today's vehicles is far more advanced than the original design produced in 1876 it still ________(2) according to the same four-stroke cycle.

During the ________(3) stroke, the piston moves downward in the cylinder, drawing air fuel with it through the open intake valve. Once the piston reaches the extent of its ________(4) travel it reverses direction to begin compressing the mixture. During this time both valves are closed. This is _______(5) as the compression stroke.

At the appropriate time, a _________(6) is produced to ignite the mixture, as the mixture burns and exerts a tremendous amount of energy on top of the piston causing it to move downward. This begins the powerstroke. At the conclusion of the power stroke a piston ______(7) direction to __________(8) the spent gases from the cylinder via the open exhaust valve. This is the final string of the cycle and is ________(9) called the exhaust stroke. Once the exhaust stroke has completed, the cycle repeats.

As you saw in the animation, the up-and-down movement of the pistons is converted to _________(10) motion of the crankshaft. This powers then transfers to the transmission to the _________(11) wheels.