I have had many bowel movements of long, strings white or clear mucus in my stool, or in place of a stool, what could it be? it's been present over a year?

Need to examine: It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. You may take a fiber laxative like Metamucil and drink enough water daily so that your urine is colorless. For the long term you may try to increase your intake of fiber foods. http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/high-fiber-foods