One should make an effort to learn English, because it is the International language, which everyone should should know.
We should learn the Universal language, to interact with other people in the world.
Also, leaning any language will make u to be a good one, in that language. You should learn English, to be good in English.
One should learn English, to do any job in any other country. One can interact with the world by English only.
Everyone didn't know all the languages. So, we should be able to learn at-least English, which is understood by all.
Hope this will help you.