Answer:
Sorry if this is multiple choice, but I have some answers!
Step-by-step explanation:
-The British Empire conquered about a quarter of the planet while in their prime, so naturally they had brought their language with them.
-Post War in the U.S started a boom in international trade, making the language even more necessary to know to trade goods.
-There is a certain hip/coolness factor to other countries with the way English can be spoken, especially since most movies and popular media are based in English due to Hollywood's infamy.
-The internet and other modern electronics were invented within America as well as the most hardware coming from the same place and using the Latin alphabet, along with major scientific leads being documented in the same language.
-English only really can grow in popularity as people who don't already speak it gain some sort of interest in visiting English speaking countries, who desire to consume English media, it evolves and changes with time so the possibility of it going out of style is scarce.
(Hope this helps!^^)