Why english is so important to us?

Answer 1

English is the language used by the most influential countries of the past approximately 1000 years, including Great Britain and the United States of America. Because of the influence on commerce, it became increasingly important for other countries to learn English in order to participate in the wealth of the commerce driven by those countries. Before globalization, languages remained fairly localized due to the limited interaction across language borders, but as the economy gradually melds into one super-economy, a common language for honest and open communications is increasingly important.

This answer does not necessarily reflect why English would be important to any specific individual, however. English may be most important because you want to do business, earn money, make new friends, communicate with distant relatives, and so on. Even those that oppose the United States of America would learn English if only to understand the enemy's communication.