Spanish has become the fastest-growing language in the 2021 year. The widespread reach of the Spanish language across Europe and the Americas has made it achieve the No.1 position in languages. With over 470 million native speakers and a growing number of non-native speakers, it is the most commonly spoken language in the world.
It is also easy to learn Spanish unlike French, German, Chinese, etc. English is also considered the most spoken language. If someone wants to learn Spanish grammar quickly and looking for the best Spanish book then must buy Spanish Grammar Book by The Olivia & Hill Press. I must say it is the best book.
English is the international business, trade, manufacturing and learning language of the world
Arabic is also very famous and fast growing language. It is spoken in Middle East and by many Muslims of the world.
As the dominant force on the planet now and into the future, it makes sense to learn Chinese as a second language. I choose Japanese as it interests me more however.
Just cause lots of people speak Mandarin and Arabic, does not mean that they're "fast growing" languages.
Spanish is taking over, because it's fairly easy to learn, it's a classical language evolved from latin, it's practical, and it doesn't sound like gibberish.