I will try to push the box.
The box changed its position when I pushed it.
I wonder if all these boxes are like this one.
Am I not strong enough, or is this box different?
I pushed it but it remains at the same location.
This is strange.
There may be an interesting phenomenon behind this.
Let me try the other two boxes.
Again one that does not change the position when I push it.
Strange.
I'm so confused right now.
I was able to make one box change its position when I pushed it while the other two boxes did not change their positions.
What about the last one?
Oh, it's like the first one.
Let me think about this for a moment.
Apparently there are two types of boxes which behave differently when I push them.
If I push a box and it changes its position, I say the box is movable.
If it remains at the same location as I try to push it, I say the box is not movable.
So far that's all I could learn about these boxes.
But I cannot say of which type a box is unless I try to push it.