Judging by the extremely quick up-and-down motion, the guy couldn't have been hung much larger than my big toe.

Then made an up-and-down motion, spreading again to show a three-foot height.

The up-and-down motion must have meant that something was wrong.

Then she nodded, not quite the human up-and-down motion but a circular bobbing of her head.

The annoying up-and-down motion of the boat across the swells had stopped.

He ran with such fluidity that there was no up-and-down motion, merely the sensation of forward movement.

He checked for the throttle and found it as an up-and-down motion of the control column.

Clyde could see the up-and-down motion of the man's fingers.

Frank made a sharp up-and-down motion with his hand.

His rump started a rough up-and-down motion as he pumped at her.