I though about it for a while.
I asked the question to myself, why do I learn English?

The answer was very very simple for me.
It was for survival.

I had no talent in math or in science, so I need to improve the basic requirement of human kind, language.

English is definitely a useful language.

I am wonering why the parents never tole their kids why do they need to learn English. Is it becuase that themselves don't know the answer too?