Third, educational quality is absolutely zero, and they do not only employ unqualified people

They do not only employ unqualified people? So, do you mean that they DO employ qualified people? What are you trying to tell us?

He's not a native speaker of English, therefore he makes the odd grammar mistake here and there. However, when it comes to a general knowledge of linguistics, you will probably find that the guy really knows his stuff and you would struggle to challenge him. Therefore, we can forgive the odd mistake.

Besides, his occasional use of 'crap' as a countable noun often proves to be a very good and mildly amusing way of putting down poor quality training centres like yours.