How does nails grow after cutting it again and again??

Dear Student 

Nails have Matrix which is responsible for growth of  nails after cutting it again and again. Each nails begins growing out of a little pocket under your skin. This is the root of the nail, and it's called Matrix. The matrix constantly makes new cells. These new cells force the old ones to get packed together and pushed up through the skin. By the time the nail pokes out of the skin, those cells are dead. That's why it doesn't hurt to cut your nails

Hope this will clear doubts about the topic.