Answer:
1) A mother pushing his son in the swings on the park, here the mother is applying the mechanical force which creates a movement on the kid.
2) Is a kid jumps on the ground, he is applying mechanical force in the ground which permits him elevate a little bit and "fight" against the gravity force.
3) Walking, when you walk, the bottom of your feet is using the friction force in the ground to impulse your body.
