1) The Olympic Games, originating in ancient Greece, were revived in 1896 and are now held every four years, bringing together athletes from around the world.

2) Chinese mythology, deeply intertwined with Chinese culture and history, includes deities such as the Jade Emperor, Guanyin, and the Monkey King (Sun Wukong). It incorporates elements of Taoism, Confucianism, and Buddhism and features legendary creatures like dragons, phoenixes, and Qilin.

3) Leonardo DiCaprio is an acclaimed American actor and environmental activist. He has starred in numerous successful films, including "Titanic," "The Revenant," and "The Wolf of Wall Street," and has been recognized with several awards, including an Academy Award.

4) The phenomenon known as "black holes" occurs when matter is crushed into an infinitely small space, creating a gravitational pull so strong that nothing can escape.