1) The word "oxygen" contains two vowels: O and E.

2) Coffee is one of the most widely consumed beverages in the world, made from the roasted seeds of the Coffea plant. It is known for its stimulating effects due to its caffeine content and is enjoyed in various forms, including espresso, cappuccino, and latte. The cultivation and preparation of coffee have evolved into an art form, with different regions and methods producing unique flavors and profiles, offering a diverse range of experiences for coffee lovers.

3) The world's tallest waterfall is Angel Falls in Venezuela, with a height of about 3,212 feet (979 meters).

4) The hibiscus flower is commonly associated with tropical regions and is the national flower of several countries, including Malaysia, South Korea, and Haiti.