This morning, this link appeared on Twitter.  Now, there is nothing wrong with practice.  However, one reason that studying English in Korea is inefficient is that there endless repetition without reason.  Here is yet another example.

It may be the case that the author is completely fluent and completely qualified to teach English.  Nevertheless, the last thing that Korean students need are drills, drills and more drills without explanation.  Koreans have been taught in this way for too long, and it has resulted in the waste of precious time.

The internet, of course, can be a powerful learning tool.  The Lost Seoul has questioned whether or not Twitter is helpful in learning English.  There is no doubt that the internet should be an invaluable resource for learning English.  However, this exercise isn't, until there are reasons given addressing why the original sentences are wrong.