Now, I am going to tell one case.
You have a grammar phobia student. He is David James. He is 21 years old. He is very diligent student. He comes to you because you have ever told him that you graduated from English Department. He wants to speak English fluently, but unfortunately he is afraid of making mistakes and studying grammar. So, as a tutor, what will you do to invite him studying English? We know grammar is one of important things in English lesson.