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

2) The Sahara Desert, located in North Africa, is the largest hot desert in the world, covering an area of about 9.2 million square kilometers (3.6 million square miles). It is characterized by vast stretches of sand dunes, rocky plateaus, and extreme temperatures.

3) The first car with air conditioning was released in 1939.

4) The sport of golf originated in Scotland and is played on courses with 18 holes, each with a designated par score.