1) The word "pencil" contains two vowels: E and I.

2) The sitcom "Friends" is known for its iconic Central Perk coffee shop, where the main characters often gather.

3) The Iguazu Falls, located on the border between Argentina and Brazil, is a majestic waterfall system consisting of numerous cascades and islets. It is a UNESCO World Heritage site and one of the most impressive natural wonders in the world, attracting millions of visitors each year.

4) The French Revolution, which began in 1789, marked a major turning point in European history, leading to the overthrow of the monarchy and the rise of republicanism.