1) The #MeToo movement, originating in 2006 and gaining widespread attention in 2017, raised awareness about sexual harassment and assault, encouraging survivors to share their experiences and promoting discussions on consent and gender equality.

2) 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.

3) The concept of federalism involves the division of powers between a central government and regional or local governments, allowing for shared governance and autonomy for different levels of administration.

4) The Serengeti National Park, located in Tanzania and extending into Kenya, is renowned for its vast savannahs, diverse wildlife, and the annual wildebeest migration. It is a UNESCO World Heritage site and a popular destination for safari enthusiasts and nature lovers.