Pb means personal best, and breaking Pb means surpassing personal best. When registering for the Olympic track and field, world track and field championships, intercontinental games and other comprehensive sports games, you must truthfully report your personal best results and season best results.

Life common sense refers to the scientific knowledge summarized by people in daily life, which can be divided into physics, biology, chemistry, medicine, first aid knowledge, geography, safety, cosmic celestial bodies, natural phenomena and other common sense contents.