Well I think the most important and useful thing is that English is one of the most spoken languages in the world. The first one is Mandarin. Some say English is the second one and others say it's Hindi. Nevertheless, Mandarin and Hindi are concentrated in their respective countries, and English is more extended.
for me i say that english language is very important cause where ever you go as long as you can speak English you can survive.Yes some people say that other countries do not speak the language but I still believe that as long us you are equip with this language you can toour around the world.