To move the body and use strength to lift things.
because it is the thing that allows you to move. Without it youm would not be able to do the most simplest things!!
allows you to move.
A system that allows energy to move in and out but not mass.
A lever allows you to magnify the force applied to an object at the expense of distance. With a lever you can move objects many times larger than you could without one, but at a slower pace.
A pulley system can change the direction of a force, making it easier to lift or move heavy objects. By distributing the force over multiple ropes and pulleys, it can also reduce the amount of force required to lift an object. This allows for more efficient use of energy in lifting objects.
You may be thinking of an "air foil", which also has the property of "lift" when oriented properly. See: http://en.wikipedia.org/wiki/Airfoil
muscles
It allows you to move your bones.
The musculeskeletal system is the organ system that allows a person to move using the muscular and skeletal system.
Muscles also help to move.
A closed system allows energy to move freely between its components, but no matter enters or leaves the system. This means that while energy can be exchanged with the surroundings, the total mass of the system remains constant.