Main points
The Contact-Time Factor. It’s a simple concept: if you want to improve your English, you have to increase the amount of contact that you have with the language.
Remember
That’s still only about 10 weeks of contact time.
That’s not just theoretical. This is how polyglots learn a new language every two years. They do something with the language every day.
We can look at that statistic from the opposite perspective:
… that is the equivalent of one hour of class in an academy; and it’s free.
300 days out of 365 days of the year, you will do 150 hours of practice during the year.
… is the equivalent of the practice that 600 hours of class in a traditional academy gives you.
you would get the same amount of practice that you get from 600 hours of class in an academy; that is, 5 years of 120 hour English courses.