Frictional force is the force which stops an object.
1.a man slips when he step on a banana peel because of its smooth surface which leesen the friction betwwen the peel and the ground.
2.a. a pencil can write on paper because there is friction between them.
b.the handles are covered with rubber sheet to increase the friction so that the hand don't slip while driving.
c.the soles wear out because of the friction between the soles and the ground.
d.because of the friction.