Here's why:

* A single force can definitely move an object. Imagine pushing a box across a floor. You are applying one force, and the box moves.

* The statement is likely referring to Newton's Third Law of Motion: This law states that for every action, there is an equal and opposite reaction. However, it's important to understand:

* These forces act on different objects. When you push the box, you exert a force on it, and the box exerts an equal and opposite force on you.

* These forces don't cancel each other out. They act on different objects, so they don't affect the motion of the same object.

To summarize:

* A single force can move an object.

* The statement about needing two forces might be referencing Newton's Third Law, which describes forces acting on *different* objects.

* The forces described in Newton's Third Law don't cancel each other out because they act on different objects.