Cases of word usage

1) to swing backwards and forwards as the pendulum of a clock does; to change between extremes of opinions etc (oscillate)

2) to move (something) backwards and forwards on the surface of another (rub)

3) (to cause something having one end or one side fixed and the other free) to move forwards an backwards or in a curve; to turn quickly (swing)

4) a game for two or four players who hit a ball with a racket backwards and forwards across a net (tennies)

5) (to cause something) to move quickly and continuously backwards and forwards (vibrate)