Complex sentence: A whirling motion is given to the spindle on the thigh or any convenient part of the body; the spindle is then dropped, twisting the yarn, which is wound on the upper part of the spindle.
Split into simpler sentences: A whirling motion is given to the spindle on the thigh or any convenient part of the body. The spindle is then dropped, twisting the yarn, which is wound on the upper part of the spindle.