Which type of knot would you use to temporarily shorten a rope length?

The sheepshank knot is specifically designed to temporarily shorten a length of rope while still maintaining the ability to untie it easily. It can create a section of slack in the middle of a rope, making it ideal for situations where you might need to adjust the length of the rope quickly for different uses without permanently altering it. This knot involves forming two bights on either side of a section of rope, which effectively shortens it while providing a secure hold.

Other knots, such as the bowline knot or figure eight knot, are generally used for creating loops or securing ends but do not allow for quick adjustments in the middle of a rope. The clove hitch is a binding knot used to attach a rope to a post or similar fixture, which also doesn't serve the purpose of temporarily shortening a rope. Thus, the choice of the sheepshank highlights its functionality in adjusting rope length while ensuring that it can be easily released later when no longer needed.